UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

 

FORM 6-K

 

REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR
15d-16 UNDER THE SECURITIES EXCHANGE ACT OF 1934

 

For the month of January 2023

 

Commission File Number: 001-40786

 

Sigma Lithium Corporation
(Translation of registrant's name into English)

 

2200 HSBC Building

885 West Georgia Street

Vancouver, British Columbia

V6C 3E8
(Address of principal executive office)

 

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F ¨      Form 40-F x

 

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  ¨

 

Note: Regulation S-T Rule 101(b)(1) only permits the submission in paper of a Form 6-K if submitted solely to provide an attached annual report to security holders.

 

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  ¨

 

Note: Regulation S-T Rule 101(b)(7) only permits the submission in paper of a Form 6-K if submitted to furnish a report or other document that the registrant foreign private issuer must furnish and make public under the laws of the jurisdiction in which the registrant is incorporated, domiciled or legally organized (the registrant's "home country"), or under the rules of the home country exchange on which the registrant's securities are traded, as long as the report or other document is not a press release, is not required to be and has not been distributed to the registrant's security holders, and, if discussing a material event, has already been the subject of a Form 6-K submission or other Commission filing on EDGAR. 

 

 

 

 

 

EXHIBIT INDEX

 

Exhibit   Description
     
99.1   Grota do Cirilo Lithium Project, Aracuai and Itinga Regions, Minas Gerais, Brazil, Updated Technical Report, dated January 16, 2023
99.2   Consent of Homero Delboni Jr.
99.3   Consent of Porfirio Cabaleiro Rodriguez
99.4   Consent of Noel O’Brien
99.5   Consent of Marc-Antoine Laporte
99.6   Consent of Jarrett Quinn

 

 

 

 

SIGNATURES

 

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

 

        Sigma Lithium Corporation    
    (Registrant)
     
Date: January 16, 2023   /s/ Ana Cristina Cabral Gardner
    Ana Cristina Cabral Gardner
    Co-Chief Executive Officer

 

 

 

 

Exhibit 99.1

 

NI 43-101 TECHNICAL REPORT
GROTA DO CIRILO LITHIUM PROJECT

 

 

GROTA DO CIRILO LITHIUM PROJECT

 

ARAÇUAÍ AND ITINGA REGIONS, MINAS GERAIS, BRAZIL

 

Updated Technical Report

 

Prepared for: Sigma Lithium Corporation

 

Prepared by:

 

Homero Delboni Jr., MAusIMM (CP), HDA Serviços S/S Ltda.

 

Marc-Antoine Laporte, P.Geo, SGS Canada Inc

 

Jarrett Quinn, P.Eng., Primero Group Americas

 

Porfirio Cabaleiro Rodriguez, (MEng), FAIG, GE21 Consultoria Mineral

 

Noel O’Brien, FAusIMM, Trinol Pty Ltd.

 

Effective Date: 31st October 2022

 

Issue Date: 16th January 2023

 

 

 

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IMPORTANT NOTICE

 

This report was prepared as an updated NI 43-101 Technical Report for Sigma Lithium Corporation (Sigma) by Primero Group Americas Inc. (a subsidiary of Primero Group Ltd), SGS Geological Services and GE21 Consultoria Mineral (collectively the Report Authors).The quality of information, conclusions, and estimates contained herein is consistent with the level of effort involved in the Report Authors' services, based on i) information available at the time of preparation, ii) data supplied by outside sources, and iii) the assumptions, conditions, and qualifications set forth in this report. This report is intended for use by Sigma subject to terms and conditions of its individual contracts with the Report Authors.

 

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Table of Contents

 

1 SUMMARY 26

 

1.1 Introduction 26
1.2 Property Description and Location 26
1.3 Accessibility, Climate, Local Resources,Infrastructure and Physiography 27
1.4 History 27
1.5 Geological Setting and Mineralization 27
1.6 Exploration 28
1.7 Drilling 29
1.8 Sample Preparation, Analyses and Security 29
1.9 Data Verification 31
1.10 Mineral Processing and Metallurgical Testing 32
1.11 Mineral Resource Estimates 33
1.12 Mineral Reserve Estimates 38
1.13 Mining Methods 43
1.14 RECOVERY Methods 44
1.15 Project Infrastructure 45
1.16 Market Studies and Contracts 47
1.17 Environmental Studies, Permitting and Social or Community Impact 48
1.18 Capital and Operating Costs 51
1.19 Economic Analysis 53
1.20 Interpretation and Conclusions 58
1.21 Recommendations 59

 

2 INTRODUCTION 60

 

2.1 Terms of Reference 60
2.2 Effective Dates 61
2.3 Qualified Persons 61
2.4 Site Visits 61
2.5 Information Source 62

 

3 RELIANCE ON OTHER EXPERTS 63

 

3.1 Marketing 63
3.2 Units and Currency 63
3.3 Environmental, Permitting and Social Licence 63
3.4 Taxation 64
3.5 Mineral Tenure 64

 

4 PROPERTY DESCRIPTION AND LOCATION 65

 

4.1 Property Description and Location 65
4.2 Mineral Tenure 66
4.3 Surface Rights 69
4.4 Agreements 70
4.5 Royalties and Encumbrances 70
4.6 QP Comment 70

 

5 ACCESSIBILITY, CLIMATE, LOCAL RESOURCES,INFRASTRUCTURE AND PHYSIOGRAPHY 71

 

5.1 Accessibility 71
5.2 Climate 71
5.3 Local Resources and Infrastructure 71
5.4 Physiography 74

 

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6 HISTORY 75

 

6.1 Project History 75
6.2 Production 76

 

7 GEOLOGICAL SETTING AND MINERALIZATION 77

 

7.1 Regional Geology 77
7.2 Local Geology 77
7.3 Property Geology 80

 

8 DEPOSIT TYPES 90

 

9 EXPLORATION 92

 

9.1 Introduction 92
9.2 Grids and Surveys 92
9.3 Geological Mapping 92
9.4 Channel Mapping 92
9.5 Trench Sampling 94
9.6 Exploration Potential 95

 

10 DRILLING 99

 

10.1 Introduction 99
10.2 Drill Type 99
10.3 Sigma Drilling Campaigns 99
10.4 Drill Hole Logging 109
10.5 Recovery 110
10.6 Drill Surveys 110
10.7 QP Comment 110

 

11 SAMPLE PREPARATION, ANALYSES AND SECURITY 111

 

11.1 Introduction 111
11.2 Sampling 111
11.3 Density Determinations 112
11.4 Analytical and Test Laboratories 113
11.5 Sample Preparation and Analysis 113
11.6 Quality Assurance and Quality Control 114
11.7 Sample Security 134
11.8 Sample Storage 134
11.9 QP Comments 135

 

12 DATA VERIFICATION 136

 

12.1 Drilling Database 136
12.2 Witness Sampling 136
12.3 QP Comments 140

 

13 MINERAL PROCESSING AND METALLURGICAL TESTING 141

 

13.1 Xuxa Metallurgical Test work (2018-19) 141
13.2 Xuxa Metallurgical Test Work (2020-2021) 151
13.3 Barreiro Metallurgical Test Work (2020-21) 168
13.4 Nezinho do Chicao Test Work (2022) 184

 

14 MINERAL RESOURCE ESTIMATES 200

 

14.1 Nezinho do Chicao Deposit 200
14.2 Xuxa Deposit 211
14.3 Barreiro Deposit 220
14.4 Murial Deposit 232
14.5 Lavra Do Meio Deposit 240

 

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15 MINERAL RESERVE ESTIMATES 251

 

15.1 Xuxa Mineral Reserves 251
15.2 Xuxa Pit Optimization Parameters 252
15.3 Xuxa Modifying Factors 255
15.4 Xuxa Pit Optimization Study 260
15.5 Xuxa Mineral Reserves Statement 266
15.6 Barreiro Mineral Reserves 267
15.7 Barreiro Pit Optimization Parameters 268
15.8 Barreiro Modifying Factors 271
15.9 Barreiro Pit Optimization Study 275
15.10 Barreiro Mineral Reserves Statement 280
15.11 Nezinho do Chicao Mineral Reserves 280
15.12 Pit Optimization Parameters 282
15.13 Modifying Factors 284
15.14 Pit Optimization Study 287
15.15 Nezinho do Chicão Mineral Reserves Statement 292

 

16 MINING METHODS 293

 

16.1 Xuxa Open Pit Mining 293
16.2 Xuxa Mine Sequencing 304
16.3 Xuxa Mine Fleet 311
16.4 Barreiro Open Pit Mining 331
16.5 Barreiro Mine Sequencing 348
16.6 Barreiro Mine Fleet 354
16.7 Nezinho do Chicão Open Pit Mining 372
16.8 Mine Sequencing 403
16.9 Mine Fleet Sizing 408

 

17 RECOVERY METHODS 424

 

17.1 Processing Overview 424
17.2 Nezinho do Chicao Trade-Off Update 424
17.3 Xuxa Process Plant (Phase 1) 426
17.4 Barreiro Process Plant (Scenario 1: Phase 2) 435
17.5 Barreiro Process Plant (Scenario 2: Phase 2) 441
17.6 Nezinho do Chicao Plant (Scenario 2: Phase 3) 441
17.7 Combined Barreiro& Nezinho do Chicao Plant (Scenario 3: Phase 2 and 3) 448

 

18 Project Infrastructure 456

 

18.2 Roads 458
18.3 Earthworks and Buried Services 459
18.4 Water Balance (Storm Water, Water Treatment) xuxa 460
18.5 Sewage 463
18.6 Built Infrastructure 463
18.7 Stockpiles 466
18.8 Waste Disposal 467
18.9 Fuel 478
18.10 Power Supply 478
18.11 Water Supply 481
18.12 Compressed Air 481
18.13 Control Systems 481
18.14 Communication Systems 482
18.15 Camps and Accommodation 482
18.16 Port Facilities 482

 

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19 MARKET STUDIES AND CONTRACTS 484

 

19.1 Lithium Demand Forecast 484
19.2 Lithium Supply Forecast 485
19.3 Lithium Price Forecast 488
19.4 Contracts and Off-Take Agreements 489

 

20 ENVIRONMENTAL STUDIES, PERMITTING AND SOCIAL OR COMMUNITY IMPACT 492

 

20.1 Environmental Considerations 492
20.2 Permitting Considerations 496
20.3 Social Considerations 498
20.4 Evaluation of Environmental Impacts and Mitigation Actions 499
20.5 Waste and Water Management 502
20.6 Relations with Stakeholders 503
20.7 Rehabilitation and Closure Planning 504
20.8 Phase 2 Barreiro Pegmatite Environmental Work 505
20.9 Phase 3 Nezinho do Chicão Environmental Works 515

 

21 CAPITAL AND OPERATING COSTS – PHASE 1 AND PHASE 2& 3 516

 

21.1 Basis of Estimate 516
21.2 Work Breakdown Structure 516
21.3 Estimate Plan 516
21.4 Capital Cost 518
21.5 Operating Costs 530

 

22 ECONOMIC ANALYSIS 537

 

22.1 Economic Assumptions 537
22.2 Phase 1 DFS Economic Analysis 539
22.3 Phase 2& 3 PFS Economic Analysis 544
22.4 Phase 1, 2& 3 Economic Analysis 549

 

23 ADJACENT PROPERTIES 554

 

24 OTHER RELEVANT DATA AND INFORMATION 555

 

24.1 Schedule for Xuxa Phase 1 555
24.2 Schedule for Barreiro Phase 2 556
24.3 Schedule for NDC Phase 3 556

 

25 INTERPRETATION AND CONCLUSIONS 557

 

25.1 Conclusions 557
25.2 Risk Evaluation 561
25.3 Opportunities 562

 

26 RECOMMENDATIONS 563

 

26.1 Geology and Resources 563
26.2 Xuxa 563
26.3 Barreiro Project Recommendations 564
26.4 Nezinho do Chicao Project Recommendations 564
26.5 Murial Project Recommendations 565

 

27 REFERENCES 566

 

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List of Tables

 

Table 1-1: NDC Deposit Mineral Resource Estimate 35
Table 1-2: Xuxa Deposit Mineral Resource Estimate 36
Table 1-3: Barreiro Deposit Mineral Resource Estimate 36
Table 1-4: Murial Deposit Mineral Resource Estimate 37
Table 1-5: Lavra do Meio Deposit Mineral Resource Estimate 37
Table 1-6: Parameters Used in Xuxa Pit Optimization 38
Table 1-7: Xuxa Mineral Reserves 39
Table 1-8: Parameters Used in Barreiro Pit Optimization 40
Table 1-9: Barreiro Mineral Reserves 41
Table 1-10: Parameters Used in NDC Pit Optimization 42
Table 1-11: Nezinho do Chicao Mineral Reserves 43
Table 1-12 – Xuxa Waste Pile Storage 46
Table 1-13: Barreiro Waste Pile Storage 46
Table 1-14: NDC Waste Pile Capacity and Surface Area 46
able 1-15 – Capital Cost Estimate Summary Phase 1 52
Table 1-16: Capital Cost Estimate Summary Phase 2& 3 52
Table 1-17: Phase 1 Operating Cost Estimate Summary 53
Table 1-18: Phase 2& 3 Operating Cost Estimate Summary 53
Table 1-19 – Base Case After-Tax NPVs 54
Table 1-20: Phase 1 Base Case Scenario Results 54
Table 1-21: Key Phase 1 Technical Assumptions 55
Table 1-22: Phase 2& 3 Base Case Scenario Results 56
Table 1-23: Key Phase 2& 3 Technical Assumptions 56
Table 1-24: Phase 1, 2& 3 Base Case Scenario Results 57
Table 1-25: Key Phase 1, 2& 3 Technical Assumptions 57
Table 4-1: Mineral Rights Description 67
Table 4-2: Property Tenure Summary 69
Table 6-1: Project History 75
Table 9-1: Channel Sampling Summary 93
Table 9-2: Grota do Cirilo Trench Sampling Summary 94
Table 9-3: Grota do Cirilo Property Prospects 95
Table 9-4: Genipapo Property Prospects 97
Table 9-5: Santa Clara Property Prospects 98
Table 10-1: Total Sigma Drill Holes to October 31, 2022 99
Table 10-2: Total Xuxa Drilling 99
Table 10-3: Xuxa Example Drill Intercept Table 100
Table 10-4: Total Barreiro Drilling 101
Table 10-5: Barreiro Example Drill Intercept Table 102
Table 10-6: Total Lavra do Meio Drilling 103
Table 10-7: Lavra do Meio Example Drill Intercept Table 104
Table 10-8: Total Murial Drilling 105
Table 10-9: Murial Example Drill Intercept Table 106
Table 10-10: Nezinho do Chicao Drilling to December 1, 2021 107
Table 10-11: Nezinho do Chicao Example Drill Intercept Table 108
Table 10-12: Total Maxixe Drilling 109
Table 11-1: Specific Gravity of Lithium-Bearing Pegmatites 113
Table 11-2: Standard Average Li Values with Analytical Error 115
Table 11-3: Check Assay Original vs Control Samples 121
Table 11-4: Check Assay Original and Control Descriptive Statistics 121

 

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Table 11-5: Standard Average Li Values with Analytical Error 122
Table 11-6: Standard Average Li Values with Analytical Error 129
Table 12-1: Witness Sample Mineralized Interval Comparison between SGS Geosol and SGS Lakefield 137
Table 12-2: Witness Sample Original vs Control Differences 138
Table 12-3: Witness Sample Original and Control Descriptive Statistics 138
Table 13-1: Chemical Analysis and WRA Results 143
Table 13-2: Bond Abrasion and Ball Mill Work Index Test Work Summary 144
Table 13-3: Average UCS and CWi 144
Table 13-4: Summary of Ore Sorter Test Work Results 145
Table 13-5: Summary of HLS Test Results on Variability Samples 146
Table 13-6: Coarse Fraction DMS results 147
Table 13-7: DMS Tailings Grades 147
Table 13-8: Fines Fraction DMS 2nd Pass SG Cut-Points 148
Table 13-9: Ultra-fine Fraction DMS Results 149
Table 13-10: Variability sample assays 153
Table 13-11: Semi-quantitative XRD analysis of the variability samples 154
Table 13-12: HLS Interpolated stage and global lithium recoveries (6% Li2O concentrate) for each variability sample 154
Table 13-13: Variability Sample 2 Global HLS Results 155
Table 13-14: Variability Sample 3 Global HLS Results 155
Table 13-15: Variability Sample 6 Global HLS Results 156
Table 13-16: Variability Sample 6 Global HLS Results with magnetic separation 156
Table 13-17: DMS and magnetic separation results by size fraction 157
Table 13-18: Var 2 Combined DMS stage results 158
Table 13-19: Var 3 Combined DMS stage results 158
Table 13-20: Var 6 Combined DMS stage results 159
Table 13-21: Var 2 Combined Global DMS results 161
Table 13-22: Var 3 Combined Global DMS results 161
Table 13-23: Var 6 Combined Global DMS results 162
Table 13-24: Summary of 2019 and 2021 DMS and magnetic separation concentrate grade and global recovery (including hypofines fraction) 163
Table 13-25: Estimates of DMS Circuit Recovery 163
Table 13-26: Summary of Global Recovery and Yield at 5.5% Li2O for 9.5 mm Top Size 168
Table 13-27: Description of Barreiro Variability Samples 170
Table 13-28: Variability Sample and Composite Sample Assays 171
Table 13-29: Semi-quantitative XRD analysis of the four variability samples and the composite sample 171
Table 13-30: Estimates of Lithium Deportment to Spodumene 172
Table 13-31: HLS Interpolated stage and global lithium recoveries (6% Li2O concentrate) for each crush size 173
Table 13-32: Semi-Quantitative XRD Analysis for Selected Samples (-10 mm crush size) 175
Table 13-33: HLS Interpolated Stage and Global Combined Lithium Recoveries (6% Li2O concentrate) for each Variability Sample 175
Table 13-34: Variability Sample 1 Global HLS Results 177
Table 13-35: Variability Sample 2 Global HLS Results 177
Table 13-36: Variability Sample 3 Global HLS Results 178
Table 13-37: Variability Sample 4 Global HLS Results 178
Table 13-38 : Coarse fraction DMS stage results 180
Table 13-39 : Fines fraction DMS stage results 180
Table 13-40 : Ultrafines fraction DMS stage results 180
Table 13-41: Global DMS results by size fraction 182
Table 13-42: Global combined DMS results 182

 

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Table 13-43: Global combined DMS results with middlings re-crush 182
Table 13-44: Summary of DMS concentrate grade and recovery 183
Table 13-45: DMS concentrate semi-quantitative XRD analysis 183
Table 13-46: Barreiro Global Recovery and Yield between 6% and 5.5% Li2O Product Grade 184
Table 13-47: Variability Sample and Composite Sample Assays 186
Table 13-48: Semi-quantitative XRD analysis of the three variability samples and the Master composite sample 186
Table 13-49: Estimates of Lithium Deportment to Spodumene and Petalite 187
Table 13-50: HLS Interpolated stage and global lithium recoveries (6% Li2O concentrate) for each crush size 187
Table 13-51: Summary of Master Composite HLS Tests with Dry Magnetic Separation for Optimum Crush Size 189
Table 13-52: High-Grade Variability Sample HLS Results 190
Table 13-53: Medium-Grade Variability Sample HLS Results 190
Table 13-54: Low-Grade Variability Sample HLS Results 191
Table 13-55: Mineral Mass Balance for Medium-Grade HLS 191
Table 13-56: Coarse fraction DMS stage results 193
Table 13-57: Fines fraction DMS stage results 193
Table 13-58: Ultrafines fraction DMS stage results 193
Table 13-59: DMS Global results (Master Composite) – 1st Trial 195
Table 13-60: DMS Global results (Master Composite) Combined – 1st Trial 196
Table 13-61: DMS Stage results (Master Composite) Combined – 1st Trial 196
Table 13-62: DMS Global results (Master Composite) – 2nd Trial 197
Table 13-63: DMS Global results (Master Composite) Combined – 2nd Trial 198
Table 13-64: DMS Stage results (Master Composite) Combined – 2nd Trial 198
Table 14-1: NDC Assay Statistics Inside Mineralized Solids 201
Table 14-2: NDC 1 m Composite Statistics 202
Table 14-3: NDC Resource Block Model Parameters 203
Table 14-4: NDC Pit Optimization Parameters 209
Table 14-5: NDC Deposit Mineral Resource Estimate 210
Table 14-6: Xuxa Assay Statistics Inside Mineralized Solids 212
Table 14-7: Xuxa 1 m Composite Statistics 212
Table 14-8: Xuxa Resource Block Model Parameters 214
Table 14-9: Xuxa Parameters for Reasonable Prospects for Eventual Economic Extraction 219
Table 14-10: Xuxa Deposit Mineral Resource Estimate 219
Table 14-11: Barreiro Assay Statistics Inside Mineralized Solids 222
Table 14-12: Barreiro 1 m Composite Statistics 222
Table 14-13: Barreiro Resource Block Model Parameters 224
Table 14-14: Barreiro Pit Optimization Parameters 230
Table 14-15: Barreiro Deposit Mineral Resource Estimate 231
Table 14-16 – Murial Assay Statistics Inside Mineralized Solids 232
Table 14-17: Murial 1 m Composite Statistics 233
Table 14-18: Murial Resource Block Model Parameters 235
Table 14-19: Murial Parameters for Reasonable Prospect for Eventual Economic Extraction 239
Table 14-20: Murial Deposit Mineral Resource Estimate 239
Table 14-21: Lavra do Meio Assay Statistics Inside Mineralized Solids 242
Table 14-22: Lavra do Meio 1 m Composite Statistics 242
Table 14-23: Lavra do Meio Resource Block Model Parameters 244
Table 14-24: Lavra do Meio Parameters for Reasonable Prospect for Eventual Economic Extraction 249
Table 14-25: Lavra do Meio Deposit Mineral Resource Estimate 249
Table 15-1: Technical and Economic Parameters Used in the Final Xuxa Pit Optimization 253

 

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Table 15-2: Xuxa Geotechnical Pit Slope Design Criteria 254
Table 15-3: Mining Recovery Versus Partial Percentage on Block Height 257
Table 15-4: Xuxa Pit Optimization Results 261
Table 15-5: Xuxa Open Pit Operational Design Parameters 263
Table 15-6: Xuxa Pit Final Optimization Ore and Waste 264
Table 15-7: Xuxa Mineral Reserves 266
Table 15-8: Technical and Economic Parameters Used in the Final Barreiro Pit Optimization 269
Table 15-9: Barreiro Geotechnical Pit Slope Design Criteria 270
Table 15-10: Barreiro Dilution Analysis 274
Table 15-11: Barreiro Nested Pit Optimization Results 276
Table 15-12: Barreiro Open Pit Operational Design Parameters 277
Table 15-13: Barreiro Pit Final Optimization Ore and Waste 279
Table 15-14: Barreiro Mineral Reserves 280
Table 15-15: Technical and Economic Parameters Used in the Final Nezinho do Chicão Pit Optimization 283
Table 15-16: NDC Geotechnical Pit Slope Design Criteria 284
Table 15-17: Dilution Analysis 287
Table 15-18: Nested Pit Optimization Results 288
Table 15-19: Parameters for the Pit Operational Design 289
Table 15-20: Final NDC Operational Pit Summary 291
Table 15-21: Nezinho do Chicão Mineral Reserves 292
Table 16-1: Xuxa Geotechnical Slope Results Designed Pit 295
Table 16-2: Xuxa Piezometer Locations and Results 299
Table 16-3: Variation of Hydraulic Conductivity and Storage According to Depth 301
Table 16-4: Comparison between Calculated and Adopted Values of K 301
Table 16-5: Calibration Parameters for Calculated vs Observed Head Values 302
Table 16-6: Xuxa Water Levels Reached in the Drawdown Numerical Model Simulation 303
Table 16-7: Simulated Dewatering Streamflow (Annual Average) 303
Table 16-8: Xuxa Designed Mine Sequencing 305
Table 16-9: Xuxa Non-Designed Mine Sequencing 306
Table 16-10: List of Main Equipment to be used in the Operation of the Xuxa Pits 313
Table 16-11: Drilling Equipment for Xuxa Pits 314
Table 16-12: Xuxa Staffing Requirement Summary 317
Table 16-13: Xuxa Preliminary Drill and Blast Plan - Ore 322
Table 16-14: Xuxa Preliminary Drill and Blast Plan – Waste, Soil and Saprolite - Weathered 323
Table 16-15: Xuxa Preliminary Drill and Blast Plan – Waste - Fresh 324
Table 16-16: Xuxa Recommended Drill and Blast Rigs 325
Table 16-17: Xuxa Preliminary Calculations for Drilling Requirements 326
Table 16-18: Xuxa Estimated Annual Consumption of Explosives - Ore 328
Table 16-19: Xuxa Estimated Annual Consumption of Explosives - Waste 329
Table 16-20: Xuxa Estimated Annual Consumption of Explosives – Combined Ore and Waste 330
Table 16-21: Uniaxial Compression Test (UCS) Results Barreiro Pit 333
Table 16-22: Direct Shear Test Results Barreiro Pit 334
Table 16-23: Barreiro Slope Stability Analysis 338
Table 16-24: Barreiro Recommended Pit Slope Geometry 342
Table 16-25: Survey results of groundwater levels in Barreiro exploration drillholes 345
Table 16-26: Depth values of saprolite-fresh rock boundary Barreiro drill holes 346
Table 16-27: Average climatic data for Araçuaí (1981-2010) 348
Table 16-28: Barreiro Designed Mine Sequence 349
Table 16-29: Barreiro Schedule of Primary Mining Equipment 355
Table 16-30: Ore and Waste Production and percentage of material to be blasted Barreiro Pit 356
Table 16-31: Drilling Equipment for Barreiro Pit 357

 

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Table 16-32: Barreiro Staffing Schedule 360
Table 16-33: Barreiro Preliminary Drill and Blast Plan - Ore 366
Table 16-34: Barreiro Preliminary Drill and Blast Plan – Waste 367
Table 16-35: Barreiro Recommended Drill Rig 368
Table 16-36: Barreiro Preliminary Calculations for Drilling Requirements 369
Table 16-37: Barreiro Estimated Annual Consumption of Explosives - Ore 371
Table 16-38: Barreiro Estimated Annual Consumption of Explosives - Waste 371
Table 16-39: Results of laboratory tests in rock (UCS), 2022 campaign 374
Table 16-40: Results of tests after outlier treatment and adopted as test parameters UCS 374
Table 16-41: Average direction of slopes in sectors and general slope geometry 375
Table 16-42: Result of limit equilibrium analysis 384
Table 16-43: Drainage Point Inspection List and Details 395
Table 16-44: Groundwater Levels in NDC Drillholes 396
Table 16-45: Holes selected for installation of piezometers in the rock mass 402
Table 16-46: Holes selected for installation of piezometers in roofing material and saprolite 402
Table 16-47: Nezinho do Chicão Mine Schedule (Dry Basis) 404
Table 16-48: Schedule of Primary Mining Equipment 410
Table 16-49: Ore and Waste Wet Basis Production and percentage of material to be blasted 411
Table 16-50: Drilling Equipment for Nezinho do Chicão Pit 412
Table 16-51: Nezinho do Chicão Staffing 415
Table 16-52: Preliminary Blasting Plan: Ore 420
Table 16-53: Preliminary Blasting Plan: Waste 421
Table 16-54: List of Selected Equipment 422
Table 17-1: High-Level Mass Balance for Scenario 1, 2 and 3 425
Table 17-2 – Xuxa Operating Parameters 432
Table 17-3: Xuxa Design Basis and Mass Balance Summary 433
Table 17-4: Xuxa Operating Hours for Main Facilities 434
Table 17-5: Barreiro Operating Parameters 439
Table 17-6: Barreiro Design Basis and Mass Balance Summary 439
Table 17-7: NDC Operating Parameters 446
Table 17-8: NDC Design Basis and Mass Balance Summary 446
Table 17-9: Combined Barreiro/NDC Operating Parameters 454
Table 17-10: Combined Barreiro/NDC Design Basis and Mass Balance Summary 454
Table 18-1 – Infrastructure Summary Table 464
Table 18-2 – Infrastructure Summary Table 465
Table 18-3: Xuxa Waste Pile Parameters for Stability Analysis 471
Table 18-4: Safety Factor from Xuxa Waste Pile Stability Analysis 471
Table 18-5: Xuxa Waste Pile Design Parameters 472
Table 18-6: Xuxa Waste Pile Capacities and Surfaces Areas 473
Table 18-7: Barreiro Waste Pile Design Parameters 474
Table 18-8: Barreiro Waste Pile Capacity and Surface Area 474
Table 18-9: Nezinho do Chicão Waste Pile Design Parameters 477
Table 18-10: Nezinho do Chicão Waste Pile Capacity and Surface Area 477
Table 18-11 – Total Process Plant Power Demand for Phase 1 480
Table 18-12: Total Process Plant Power Demand for Phase 2& 3 480
Table 19-1: Delivery Schedule Under the LGES Offtake Agreement 490
Table 20-1 – Granted Licences and Leases 493
Table 20-2 – Baseline Studies 494
Table 20-3 – Applicable Environmental Compensation 496
Table 20-4 – Environmental Impact Minimization Measures 500
Table 20-5 – Environmental Impact Minimization Measures 505

 

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Table 21-1 – Quoted Currency Exchange Rates 518
Table 21-2 – Phase 1 Concentrator Capital Cost Estimate Summary 519
Table 21-3 Phase 2& 3 Concentrator Capital Cost Estimate Summary 522
Table 21-4: Process Plant Material Quantity Summary 525
Table 21-5: Capital Cost Estimate Basis – Process Plant 525
Table 21-6 – Contingency Requirements 527
Table 21-7 – Summary of Tax applied to the CAPEX 528
Table 21-8 – Phase 1 Estimated Capital Mining Cost 530
Table 21-9: Phase 2& 3 Estimated Capital Mining Cost 530
Table 21-10: Phase 1 OPEX Processing Cost Summary 531
Table 21-11: Phase 2& 3 OPEX Processing Cost Summary 531
Table 21-12: Phase 1 Processing Plant OPEX Cost Summary Breakdown 531
Table 21-13: Phase 2& 3 Processing Plant OPEX Cost Summary Breakdown 532
Table 21-14: Labour Summary 533
Table 21-15: Phase 1 Mining OPEX Costs 536
Table 21-16: Phase 2& 3 Mining OPEX Costs 536
Table 22-1 – Base Case After-Tax NPVs 537
Table 22-2: Phase 1 Base Case Scenario Results 539
Table 22-3: Key Phase 1 Technical Assumptions 539
Table 22-4: Phase 1 Estimated Revenue and Operating Costs 541
Table 22-5: Phase 2& 3 Base Case Scenario Results 544
Table 22-6: Key Phase 2& 3 Technical Assumptions 544
Table 22-7: Phase 2& 3 Estimated Revenue and Operating Costs 546
Table 22-8: Phase 1, 2& 3 Base Case Scenario Results 549
Table 22-9: Key Phase 1, 2& 3 Technical Assumptions 549
Table 22-10: Phase 1, 2& 3 Estimated Revenue and Operating Costs 551
Table 25-1 – Capital Cost Estimate Summary Phase 1 560
Table 25-2: Capital Cost Estimate Summary Phase 2& 3 560
Table 25-3 – Phase 1 Operating Cost Estimate Summary 561
Table 25-4: Phase 2& 3 Operating Cost Estimate Summary 561

 

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List of Figures

 

Figure 2-1: Project Location 60
Figure 4-1: Project Properties - Genipapo, Grota do Cirilo, Santa Clara and São José 65
Figure 4-2: Project Mineral Rights, North and South Complexes 68
Figure 5-1: Aerial View, Current Project Infrastructure 72
Figure 5-2: Field Office (location 6 in Figure 5-2) 72
Figure 5-3: SMSA Pilot Plant 73
Figure 5-4: Lithium Metallurgical Test Phase Production Plant 73
Figure 5-5: Photo Showing Typical Vegetation Within Project Area 74
Figure 7-1: Regional Geologic Map (after Pedrosa-Soares et al., 2001) 78
Figure 7-2: Local Geology Map, Northern Complex 79
Figure 7-3: Historic Workings and Pegmatite Dike Swarms within Grota Do Cirilo Property 80
Figure 7-4: Xuxa Cross Section(looking northeast) 81
Figure 7-5: Barreiro Cross Section(looking northeast) 82
Figure 7-6: Lavra do Meio Cross Section(looking north) 83
Figure 7-7: Nezinho Do Chicao Cross Section(looking northeast) 84
Figure 7-8: Murial Cross Section(looking north) 85
Figure 7-9: Historical Workings within São José Property 86
Figure 7-10: Macro Crystals at Lavra Ramon 87
Figure 7-11: Samambaia Plan Map 88
Figure 7-12: Ananias Plan Map 89
Figure 8-1: Generalized Schematic Representation LCT Pegmatite 91
Figure 9-1: Grota do Cirilo Satellite Image 93
Figure 9-2: Channel Samples at Murial Mine 94
Figure 10-1: Plan View of the Drilling at Xuxa (2017 blue collars and 2018 black collars) 100
Figure 10-2: Longitudinal View of the Drilling at Xuxa 101
Figure 10-3: Plan View of the Drilling at Barreiro 102
Figure 10-4: Longitudinal View of the Drilling at Barreiro 103
Figure 10-5 – Plan View of the Drilling at Lavra do Meio 104
Figure 10-6: Longitudinal View of the Drilling at Lavra do Meio 105
Figure 10-7: Plan View of the Drilling at Murial 106
Figure 10-8: Longitudinal View of the Drilling at Murial 107
Figure 10-9: Plan View of the Drilling at Nezinho do Chicao 108
Figure 10-10: Longitudinal View of the Drilling at Nezinho do Chicao 108
Figure 10-11: Maxixe Drill Hole Location Plan 109
Figure 11-1: Standard Sample Analysis Results for the 2017–2018 Batch with Standard AMIS0338 115
Figure 11-2: Standard Sample Analyses Results for the 2017–2018 Batch with Standard AMIS0339 116
Figure 11-3: Standard Sample Analyses Results for the 2017–2018 Batch with Standard AMIS0341 116
Figure 11-4: Standard Sample Analyses Results for the 2017–2018 Batch with Standard AMIS0342 117
Figure 11-5: Standard Sample Analyses Results for the 2017–2018 Batch with Standard AMIS0343 117
Figure 11-6: Standard Sample Analyses Results for the 2017–2018 Batch with Standard AMIS0408 118
Figure 11-7: Blank Sample Analyses from the 2017–2018 Campaign 119
Figure 11-8: Scatterplot of Core Duplicates 120
Figure 11-9: Correlation Between Original Samples and Pulp Duplicates 120
Figure 11-10: Check Assay Correlation Between Original Samples and Pulp Duplicates 121
Figure 11-11: Check Assay Distribution of the Difference Between Original Results and Pulp Duplicates 122
Figure 11-12: Standard Sample Analysis Results for the 2021 Batch with Standard AMIS0341 123
Figure 11-13: Standard Sample Analysis Results for the 2021 Batch with Standard AMIS0342 123
Figure 11-14: Standard Sample Analysis Results for the 2021 Batch with Standard AMIS0343 124
Figure 11-15: Standard Sample Analysis Results for the 2021 Batch with Standard AMIS0408 124

 

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Figure 11-16: Blank Sample Analyses from the 2021 Campaign 125
Figure 11-17: Correlation Between 2021 Original Samples and Coarse Duplicates 126
Figure 11-18: Correlation Between 2021 Original Samples and Pulp Duplicates 127
Figure 11-19: 2021 Check Assay Correlation Between SGS Originals and ALS Duplicates 128
Figure 11-20: Check Assay Distribution of the Difference Between SGS Originals and ALS Duplicates 128
Figure 11-21: Standard Sample Analysis Results for the 2021-2022 NDC Batch with Standard AMIS0341 129
Figure 11-22: Standard Sample Analysis Results for the 2021-2022 NDC Batch with Standard AMIS0342 130
Figure 11-23: Standard Sample Analysis Results for the 2021-2022 NDC Batch with Standard AMIS0343 130
Figure 11-24: Standard Sample Analysis Results for the 2021-2022 NDC Batch with Standard AMIS0343 131
Figure 11-25: Blank Sample Analyses from the 2021-2022 NDC Campaign 132
Figure 11-26: Correlation Between 2021-2022 NDC Original Samples and Coarse Duplicates 133
Figure 11-27: Correlation Between 2021-2022 NDC Original Samples and Pulp Duplicates 133
Figure 11-28: 2021-2022 NDC Check Assay Correlation Between SGS Originals and ALS Duplicates 134
Figure 12-1: Witness Sample Original vs Control Sample Differences 138
Figure 12-2: Witness Sample Original vs Control Sample Differences Frequency Distribution 139
Figure 12-3: Witness Sample Original vs Control Sample Differences Correlation Analysis 139
Figure 13-1: Overview of Typical Stage 1 Test work Flowsheet 141
Figure 13-2: Sample Preparation Diagram for Stage 1 Variability Samples 142
Figure 13-3: Effect of Combining Coarse DMS and -3.3 mm Middlings HLS Concentrates 148
Figure 13-4: Xuxa Main Pegmatite and Second Pegmatite Sampled in 2018 151
Figure 13-5: Petalite Distribution (%) in Xuxa Block Model (Plan View Looking North) 152
Figure 13-6: Comparative Results for 5.5% and 6.0% Li2O Global Recovery for 9.5 mm Top Size 165
Figure 13-7: Relative Increase in Global Li2O Recovery for 9.5 mm Top Size 166
Figure 13-8: Comparative Results for 5.5% and 6.0% Li2O Global Yield for 9.5 mm Top Size 167
Figure 13-9: Relative Increase in Global Li2O Yield for 9.5 mm Top Size 168
Figure 13-10: Lithium (Li2O) Grade and Localization of the Drill Holes used to produce the Barreiro Variability Samples 169
Figure 13-11: BWi of the Composite Sample compared to the SGS Database 172
Figure 13-12: Ai of Var 3 compared to the SGS Database 173
Figure 13-13: Cumulative Lithium Grade - Stage Recovery Curves for HLS Tests 174
Figure 13-14: Cumulative Lithium Grade – Global Recovery Curves for HLS Tests 174
Figure 13-15: Lithium (Li2O) Grade and Localization of the Drill Holes used to produce the NDC Variability Samples 185
Figure 13-16: Master Composite Cumulative Lithium Grade - Stage Recovery Curves for HLS Tests 188
Figure 13-17: Master Composite Cumulative Lithium Grade - Global Recovery Curves for HLS Tests 188
Figure 14-1: NDC Drill Hole Collar Locations 201
Figure 14-2: NDC Pegmatite Solid (looking west-northwest) 203
Figure 14-3: NDC Combined Correlogram 204
Figure 14-4: Isometric View of NDC Search Ellipsoids 205
Figure 14-5: Isometric View of the NDC Interpolated Block Model 205
Figure 14-6: Statistical Comparison of NDC Assay, Composite and Block Data 206
Figure 14-7: Comparison NDC Block Values Versus Composites Inside Blocks 207
Figure 14-8: NDC Block Model Classification 208
Figure 14-9: NDC Deposit Mineral Resource Block Grades and Revenue Factor 1 Pit 209
Figure 14-10: Xuxa Drill Hole Collar Locations (2017 collars shown in blue and 2018 collars shown in black) 211
Figure 14-11: Xuxa 1 m Composite Histogram 213
Figure 14-12: Xuxa Pegmatite Solid (looking southeast) 214
Figure 14-13: Xuxa Combined Correlogram 215
Figure 14-14: Isometric View of Xuxa Search Ellipsoids 216
Figure 14-15: Isometric View of the Xuxa Interpolated Block Model 216

 

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Figure 14-16: Statistical Comparison of Xuxa Assay, Composite and Block Data 217
Figure 14-17: Comparison Xuxa Block Values Versus Composites Inside Blocks 217
Figure 14-18: Xuxa Block Model Classification 218
Figure 14-19: Barreiro Drillhole Collar Locations 221
Figure 14-20: Barreiro 1 m Composite Histogram 223
Figure 14-21: Sectional Interpretations of the Barreiro Pegmatite Unit (looking north and west) 224
Figure 14-22: Barreiro Combined Correlogram 225
Figure 14-23: Isometric View of Barreiro Search Ellipses 226
Figure 14-24: Isometric View of the Barreiro Interpolated Block Model 226
Figure 14-25: Statistical Comparison of Barreiro Assay, Composite and Block Data 227
Figure 14-26: Barreiro Block Values Versus Composites Inside Those Blocks 227
Figure 14-27: Barreiro Block Model Classification 229
Figure 14-28: Isometric View Looking Northeast: Barreiro Deposit Mineral Resource Block Grades and Revenue Factor 1 Pit 230
Figure 14-29: Murial Drill Hole Collar Locations 232
Figure 14-30: Murial 1 m Composite Histogram 233
Figure 14-31: Murial Pegmatite Solid (looking west) 234
Figure 14-32: Isometric View of Murial Search Ellipsoids 236
Figure 14-33: Isometric View of Murial Interpolated Block Model 236
Figure 14-34: Statistical Comparison of Murial Assay, Composite and Block Data 237
Figure 14-35: Murial Block Values Versus Composites Inside Those Blocks 237
Figure 14-36: Murial Block Model Classification 238
Figure 14-37: Lavra Do Meio Drill Hole Collar Locations 241
Figure 14-38: Lavra do Meio 1 m Composite Histogram 243
Figure 14-39: Lavra do Meio Pegmatite Solid (looking west) 244
Figure 14-40: Lavra do Meio Combined Correlogram 245
Figure 14-41: Isometric View of Lavra do Meio Search Ellipses 246
Figure 14-42: Isometric View of Lavra Do Meio Interpolated Block Model 246
Figure 14-43: Statistical Comparison of Lavra Do Meio Assay, Composite and Block Data 247
Figure 14-44: Lavra Do Meio Block Values Versus Composites Inside Those Blocks 247
Figure 14-45: Lavra Do Meio Block Model Classification 248
Figure 15-1: Final Xuxa Mine Configuration 252
Figure 15-2: Xuxa North and South Pit Geotechnical Sectors 254
Figure 15-3: Grade x Tonnage Curve with Selectivity Results Based on Local Uniform Conditioning Estimate 256
Figure 15-4: Cross-Section Showing the Original Pegmatite (white line) and the One Reduced At 1 M from the Edge (brown line). Blocks are Coloured Blue to Red in Relation to their Partial Percentage within the Reduced Solid (Blue = 0%, Red = 100%) 258
Figure 15-5: Schematic Representation of the Dilution Analysis 258
Figure 15-6: Xuxa Tonnage vs Partial Percentage – Dilution – 5 m 259
Figure 15-7: Tonnage vs Partial Percentage – Dilution – 1 m 259
Figure 15-8: Tonnage vs Partial Percentage – Solid Internal Dilution – 5 m 260
Figure 15-9: Pit by Pit Graph of Optimization Results 262
Figure 15-10: Xuxa Pit Wall Configuration 263
Figure 15-11: Xuxa Pit Ramp Design 264
Figure 15-12: Xuxa Final Optimized Pit Design 265
Figure 15-13: Final Barreiro Mine Configuration 268
Figure 15-14: Barreiro Pit Geotechnical Sectors 270
Figure 15-15: Barreiro Grade x Tonnage Curve with Selectivity Results Based on Local Uniform Conditioning Estimate 272

 

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Figure 15-16: Cross-Section Showing the Original Pegmatite (brown line) and the One Reduced At 1 M from the Edge (white line). Blocks are Coloured Blue to Red in Relation to their Partial Percentage within the Reduced Solid (Blue = 0%, Red = 100%) 273
Figure 15-17: Schematic Representation of the Dilution Analysis 274
Figure 15-18: Barreiro Tonnage vs Partial Percentage Curves 275
Figure 15-19: Barreiro Nested Pit Tonnage and NPV 276
Figure 15-20: Barreiro Pit Wall Configuration 278
Figure 15-21: Barreiro Pit Ramp Design 278
Figure 15-22: Barreiro Final Operational Pit Design 279
Figure 15-23: Final Nezinho do Chicão Mine Configuration 282
Figure 15-24: Cross-Section Showing the Original Pegmatite and the One Reduced At 1 m from the Edge. Blocks are Coloured Blue to Red in Relation to their Partial Percentage within the Reduced Solid (Blue = 0%, Red = 100%) 286
Figure 15-25: Bench Cross-Section 286
Figure 15-26: Tonnage vs Partial Percentage Curves 287
Figure 15-27: Nested Pits Tonnage and NPV Graph 289
Figure 15-28: Pit Wall Configuration 290
Figure 15-29: Ramp Design 290
Figure 15-30: Final Operational NDC Pit 291
Figure 16-1: Kinematic Analysis of Sector A, Xuxa North Pit 293
Figure 16-2: Xuxa North Pit, Sector A Stability Analysis, FS=1.47 294
Figure 16-3: Xuxa North Pit, Sector C Stability Analysis, FS=1.56 294
Figure 16-4: Xuxa North and South Pits with Geotechnical Sectors 295
Figure 16-5: Regional Hydrogeological Conceptual Model 296
Figure 16-6: Xuxa North and South Pits Separated by Piaui River 297
Figure 16-7: Potentiometric Map of the Xuxa Pit Region 298
Figure 16-8: Relationship between RQD and Depth Evaluated in the Block Model for the Proposed Pits 300
Figure 16-9: Steady-State Calibration Graph of Calculated vs Observed Head Values 302
Figure 16-10: Equipotential Surface of Groundwater Level in Year-9 Simulation Plan 304
Figure 16-11: Xuxa North and South Pits Year 1 307
Figure 16-12: Xuxa North and South Pits Year 2 308
Figure 16-13: Xuxa North and South Pits Year 3 308
Figure 16-14: Xuxa North and South Pits Year 4 309
Figure 16-15: Xuxa North and South Pits Year 5 309
Figure 16-16: Xuxa North and South Pits Year 6 310
Figure 16-17: Xuxa North and South Pits Year 7 310
Figure 16-18: Xuxa North and South Pits Year 8 311
Figure 16-19: Explosives Magazines in Container 315
Figure 16-20: Example of Ammonium Nitrate Emulsion Storage Structure 316
Figure 16-21: Schematic of Wash Ramp Oil-Water Separator 319
Figure 16-22: Schematic of Solid Waste Temporary Storage Facility 320
Figure 16-23: Image Analysis and Calculation of Granulometric Distribution 331
Figure 16-24: OPTV-derived stereogram showing two main joint structures at Barreiro 333
Figure 16-25: Barreiro Pit Sectorization 334
Figure 16-26: Barreiro kinematic analysis for sector 1 with 5% planar rupture occurring 335
Figure 16-27: Barreiro kinematic analysis for sector 1 with 4% planar rupture occurring 336
Figure 16-28: Barreiro kinematic analysis for sector 3 with 4% planar rupture occurring 336
Figure 16-29: Barreiro kinematic analysis for sector 4 with 4% planar rupture occurring 337
Figure 16-30: Barreiro kinematic analysis for sector 5 with 5% planar rupture occurring 337
Figure 16-31: Barreiro Kinematic analysis for sector 5 with 30% planar rupture occurring 338
Figure 16-32: Analysis of section 01 with FS = 1.92 339

 

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Figure 16-33: Analysis of section 02 with FS = 1.43 339
Figure 16-34: Analysis of section 03 with FS = 1.80 340
Figure 16-35: Analysis of section 04 with FS = 1.99 340
Figure 16-36: Analysis of section 05 with FS = 2.18 341
Figure 16-37: Jequitinhonha River Basin in Minas Gerais state, Brazil 343
Figure 16-38: Route map and drainage points inspected in the Barreiro area 344
Figure 16-39: Drill hole locations and potentiometric map of the Barreiro area 345
Figure 16-40: Barreiro geotechnical drill hole locations 347
Figure 16-41: Barreiro Pit Year 1 350
Figure 16-42: Barreiro Pit Year 2 350
Figure 16-43: Barreiro Pit Year 3 351
Figure 16-44: Barreiro Pit Year 4 351
Figure 16-45: Barreiro Pit Year 5 352
Figure 16-46: Barreiro Pit Year 6 352
Figure 16-47: Barreiro Pit Year 10 353
Figure 16-48: Barreiro Pit Year 12 353
Figure 16-49: Explosives Magazines in Container 358
Figure 16-50: Example of Ammonium Nitrate Emulsion Storage Structure 359
Figure 16-51: Schematic of Wash Ramp Oil-Water Separator 363
Figure 16-52: Schematic of Solid Waste Temporary Storage Facility 364
Figure 16-53: Image Analysis and Calculation of Granulometric Distribution 372
Figure 16-54: OPTV-derived stereogram showing two main joint structures at Nezinho do Chicão 373
Figure 16-55: Nezinho do Chicão Pit Sectors (Green) and Stability Analysis Sections (Black) 375
Figure 16-56: Kinematic analysis for sector 1, planar rupture, face angle 376
Figure 16-57: Kinematic analysis for sector 1, planar rupture, general angle 376
Figure 16-58: Kinematic analysis for sector 2, planar rupture, face angle 377
Figure 16-59: Kinematic analysis for sector 2, toppling failure 377
Figure 16-60: Kinematic analysis for sector 3, planar rupture, face angle 378
Figure 16-61: Kinematic analysis for sector 3, toppling failure 378
Figure 16-62: Kinematic analysis for sector 4, planar rupture, face angle 379
Figure 16-63: Kinematic analysis for sector 4, toppling failure 379
Figure 16-64: Kinematic analysis for sector 5, planar rupture, face angle 380
Figure 16-65: Kinematic analysis for sector 5, toppling failure 380
Figure 16-66: Kinematic analysis for sector 6, planar rupture, face angle 381
Figure 16-67: Kinematic analysis for sector 6, toppling failure 381
Figure 16-68: Kinematic analysis for sector 7, planar rupture, face angle 382
Figure 16-69: Kinematic analysis for sector 7, toppling failure 382
Figure 16-70: Kinematic analysis for sector 8, planar rupture, face angle 383
Figure 16-71: Kinematic analysis for sector 8 toppling failure 383
Figure 16-72: Sector 3 section 1 SF = 1.59 385
Figure 16-73: Sector 3 section 2 SF = 1.33 385
Figure 16-74: Sector 3 section 1 SF = 1.37 386
Figure 16-75: Sector 2 section 4 SF = 1.68 386
Figure 16-76: Sector 3 section 5 SF= 1.37 387
Figure 16-77: Sector 3 section 6 SF = 1.31 387
Figure 16-78: Sector 8 section 7 SF= 1.63/1.37 388
Figure 16-79: Sector 5 section 8 SF = 1.38 388
Figure 16-80: Sector 6 section 9 SF = 1.54 389
Figure 16-81: Sector 7 section 10 SF = 1.33 389
Figure 16-82: Jequitinhonha River Basin in Minas Gerais state, Brazil 390
Figure 16-83: Barreiro and NDC pit and waste dump arrangement in relation to Piauí River 391

 

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Figure 16-84: Regional Hydrogeological Conceptual Model 392
Figure 16-85: Master Plan- Grota do Cirilo Project 393
Figure 16-86: Route Map and Drainage Points Inspected 394
Figure 16-87: NDC Drillhole Location Map 398
Figure 16-88: NDC Potentiometric Map 398
Figure 16-89: Depth variation between weathered material (soil/saprolite) and bedrock. (Mean in red). 399
Figure 16-90: Zone selected for verification of drillholes (RQD less than 70%). 400
Figure 16-91: Proposed locations of piezometers 403
Figure 16-92: Pit Nezinho do Chicão - Year 01 405
Figure 16-93: Pit Nezinho do Chicão - Year 02 405
Figure 16-94: Pit Nezinho do Chicão - Year 03 406
Figure 16-95: Pit Nezinho do Chicão - Year 04 406
Figure 16-96: Pit Nezinho do Chicão - Year 05 407
Figure 16-97: Pit Nezinho do Chicão - Year 10 407
Figure 16-98: Pit Nezinho do Chicão - Year 12- Final Pit 408
Figure 17-1: Xuxa Process Plant 426
Figure 17-2: Block Flow Diagram for Xuxa Crushing Circuit and DMS Plant 428
Figure 17-3: Sigma Crushing and DMS Plant Overview 429
Figure 17-4: Sigma Primary Crushing Facility and Crushed Ore Bin 430
Figure 17-5: Sigma Xuxa DMS Plant and Product Stockpiles 431
Figure 17-6: Xuxa and Barreiro Process Plant Layout (2021 Design) 435
Figure 17-7: Block Flow Diagram for the Barreiro Crushing Circuit and DMS Plant 437
Figure 17-8: Xuxa (Top), Barreiro (Middle), and Nezinho do Chicao (Bottom) Process Plant Layout (2022) 442
Figure 17-9: Block Flow Diagram for the NDC Crushing Circuit and DMS Plant 444
Figure 17-10: Xuxa (Top Phase 1) and Combined Barreiro/NDC (Bottom Phase 2) Process Plant Layout (2022) 449
Figure 17-11: Block Flow Diagram for the Combined Barreiro/NDC Crushing Circuit and DMS Plant 451
Figure 18-1– Sigma Lithium Project General Layout Plan for Xuxa 456
Figure 18-2– Overall Site Plan 457
Figure 18-3: Schematic of the proposed municipal road upgrades 458
Figure 18-4: Proposed municipal access road and community bypass road 458
Figure 18-5 – Proposed Bridge Location Xuxa Mine 459
Figure 18-6 – Xuxa Mine Water Balance 461
Figure 18-7 – Intake Water / Water Treatment 463
Figure 18-8: Conceptual Representation of Workshop Areas 466
Figure 18-9: Xuxa Waste Piles Location Map 468
Figure 18-10: Xuxa Waste Piles Geotechnical Sampling Locations 469
Figure 18-11: Constructive Sequencing of the 340 M Level of the Waste Pile Berm 470
Figure 18-12: Stability Analysis Section AA for Xuxa Waste Pile 03 472
Figure 18-13: Proposed Location of Barreiro Waste Dump 473
Figure 18-14: Mine Configuration Showing Xuxa and Barreiro Pits and Sigma Processing Plant 475
Figure 18-15: Nezinho do Chicão Waste Dump Location 476
Figure 18-16: Mine Configuration Showing Xuxa, Barreiro and Nezinho do Chicão Pits and Sigma Processing Plant 478
Figure 18-17 – Product Transport Routing from Xuxa to Ilhéus 483
Figure 19-1: Lithium Supply-Demand Forecast (Benchmark Market Intelligence 2022) 484
Figure 19-2: Lithium Demand Breakdown by End-Use 2022 (Benchmark Market Intelligence 2022) 485
Figure 19-3: Electric Vehicle Sales as a Share of Total Cars (Benchmark Market Intelligence 2022) 485
Figure 19-4: Lithium Feedstock Supply Forecast (Benchmark Market Intelligence 2022) 486

 

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Figure 19-5 Lithium Chemical Supply Breakdown (Benchmark Market Intelligence 2022) 486
Figure 19-6: Long-Term Supply C1 Lithium Carbonate Cost Curve 2030 (Benchmark Market Intelligence 2022) 487
Figure 19-7: Battery-Grade Lithium Chemical Price Forecast (Benchmark Market Intelligence 2022) 488
Figure 19-8: Spodumene Price Forecast (Benchmark Market Intelligence 2022) 489
Figure 20-1 – Location of Areas of Interest and Properties 498
Figure 20-2: Sigma Wildlife Rehabilitation Centre and Seedling Nursery 502
Figure 20-3: Avifauna: A) Nest of Red Ovenbird; individual of B) Red-Cowled Cardinal, C) Grassland Sparrow; D) Smooth-billed Ani; E) Rufous-collared Sparrow; F) Tropical Kingbird; G) Burrowing Owl and H) Yellow-chevroned Parakeet. 508
Figure 20-4: Herpetofauna: A) Neotropical Ameiva, B) Tropidurus oreadicus, C) Leptodactilus fuscus; D) Tegu; E) Rhinella granulosa and F) Rhinellaschneideri. 508
Figure 20-5: Terrestrial mammalian fauna: A) wild dog; B) skunk; C) big-eared opossums; and D) footprint of Procyon cancrivorus. 509
Figure 20-6 – Project Status Plan with Mining Applications 510
Figure 22-1: Spodumene Concentrate Price Forecast 538
Figure 22-2: : Phase 1 After-Tax Cash Flow and Cumulative Cash Flow Profile @ 5.5% SC 540
Figure 22-3 : Phase 1 Financial Model Summary @ 5.5% Li2O SC 542
Figure 22-4: Phase 1 After-Tax NPV Sensitivity Analysis @ 5.5% Li2O SC (US$ B) 543
Figure 22-5: Phase 1 After-Tax IRR Sensitivity Analysis @ 5.5% Li2O SC (%) 543
Figure 22-6: Phase 2& 3 After-Tax Cash Flow and Cumulative Cash Flow Profile @ 5.5% Li2O SC 545
Figure 22-7: Phase 2& 3 Financial Model Summary @ 5.5% Li2O SC 547
Figure 22-8: Phase 2& 3 After-Tax NPV Sensitivity Analysis @ 5.5% Li2O SC (US$ B) 548
Figure 22-9: Phase 2& 3 After-Tax IRR Sensitivity Analysis @ 5.5% Li2O SC (%) 548
Figure 22-10: Phase 1, 2& 3 After-Tax Cash Flow and Cumulative Cash Flow Profile @ 5.5% Li2O SC 550
Figure 22-11: Phase 1, 2& 3 Financial Model Summary @ 5.5% Li2O SC 552
Figure 22-12: Phase 1, 2& 3 After-Tax NPV Sensitivity Analysis @ 5.5% Li2O SC (US$ B) 553
Figure 22-13: Phase 1, 2& 3 After-Tax IRR Sensitivity Analysis @ 5.5% Li2O SC (%) 553
Figure 24-1: Xuxa Schedule 555

 

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CERTIFICATE OF AUTHOR

HOMERO DELBONI JR

 

I, Homero Delboni Jr, B.E., M.Eng.Sc., Ph.D., MAusIMM (CP) of São Paulo, Brazil, do hereby certify:

 

1.I am a Senior Consultant of HDA Serviços S/S Ltda., Alameda Casa Branca, 755 cj. 161 Sao Paulo, SP 01408-001 Brazil

 

2.This certificate applies to the Technical Report entitled “Grota do Cirilo Lithium Project, Aracuai and Itinga Regions, Minas Gerais, Brazil, Updated Technical Report.” with an effective date of 31st October 2022.

 

3.I graduated with a Bachelor of Engineering Degree in Mining and Minerals Processing from The University of Sao Paulo (Brazil) in 1983, concluded a Master’s in Engineering in Minerals Processing in The University of Sao Paulo (Brazil) in 1989 and obtained a Ph.D. in Minerals Processing Engineering at The University of Queensland – Julius Kruttschnitt Mineral Research Centre, Brisbane (Australia) in 1999.

 

4.I am a Member (#112813) and Chartered Professional in Metallurgy of the Australian Institute of Mining and Metallurgy – MAusIMM – CP (Metallurgy). I have worked as a Minerals Processing engineer for a total of 39 years since my graduation from university.

 

5.I have read the definition of Qualified Person set out in the National Instrument 43-101 (Instrument) and certify that by reason of my education, affiliation with a professional association and past relevant work experiences, I fulfil the requirement to be an independent qualified person for the purposes of NI 43-101.

 

6.I have read NI 43-101 and I have participated in the preparation of this Technical Report, and I am responsible for Section 18, excluding sub-sections 18.4 and 18.8, which have been prepared in compliance with NI 43-101.

 

7.I am independent of Sigma Lithium Resources Corporation as defined by Section 1.5 of the Instrument. I do not have prior involvement with the properties that are the subject of the technical report.

 

8.As of the effective date of the Technical Report, to the best of my knowledge, information and belief, the sections of the technical report for which I am responsible contain all scientific and technical information that is required to be disclosed to make the technical report not misleading.

 

Signed and dated this 16th January 2023 at São Paulo, SP - Brazil.

 

“Signed and sealed” Homero Delboni Jr, Ph.D., MAusIMM (CP)

 

   
Homero Delboni Jr, B.E., M.Eng.Sc., Ph.D., MAusIMM – CP (Metallurgy)  

 

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CERTIFICATE OF AUTHOR
MARC-ANTOINE LAPORTE

 

I, Marc-Antoine Laporte, P.Geo., M.Sc., of Québec, Québec, do hereby certify:

 

1.I am a senior geologist with SGS Canada Inc (Geological Services) with a business address at 125 rue Fortin, Suite 100, Quebec City, Quebec, G1M 3M2.

 

2.This certificate applies to the Technical Report entitled “Grota do Cirilo Lithium Project, Aracuai and Itinga Regions, Minas Gerais, Brazil, Updated Technical Report.” with an effective date of 31st October 2022.

 

3.I am a graduate of Université Laval (2004 and 2008) in Earth Sciences. I am a member in good standing of Ordre des Géologues du Québec (#1347). I have worked as a geologist continuously since my graduation.

 

4.I have read the definition of Qualified Person set out in the National Instrument 43-101 (NI 43-101) and certify that by reason of my education, affiliation with a professional association and past relevant work experiences, I fulfil the requirement to be an independent qualified person for the purposes of NI 43-101.

 

5.My most recent personal inspection of the Project was on October 18-21, 2021.

 

6.I have read NI 43-101 and I have participated in the preparation of this Technical Report and am responsible for Sections 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 23 and the applicable parts of sections 1, 2, 25, 26 and 27, each of which has been prepared in accordance with NI 43-101.

 

7.I am independent of Sigma Lithium Corporation as defined by Section 1.5 of the Instrument. I don’t have any prior involvement with the property that is the subject of the technical report.

 

8.As of the effective date of the Technical Report, to the best of my knowledge, information and belief, the sections of the technical report for which I am responsible contain all scientific and technical information that is required to be disclosed to make the technical report not misleading.

 

Signed and dated this 16th January 2023 at Quebec City, Quebec.

 

“Signed and sealed” Marc-Antoine Laporte, P.Geo., M.Sc.

 

   
Marc-Antoine Laporte, P.Geo., Senior Geologist  
SGS Canada Inc  

 

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CERTIFICATE OF AUTHOR

JARRETT QUINN

 

I, Jarrett Quinn, P.Eng., Ph.D., of Montréal, Québec, do hereby certify:

 

1.I am a Consulting Process Engineer for Primero Group Americas Inc. with a business address at 1450 - 1801 McGill College, Montréal, Québec, H3A 2N4.

 

2.This certificate applies to the Technical Report entitled “Grota do Cirilo Lithium Project, Aracuai and Itinga Regions, Minas Gerais, Brazil, Updated Technical Report.” with an effective date of 31st October 2022.

 

3.I am a graduate of McGill University (B.Eng. 2004, M.Eng. 2006, and Ph.D. 2014) in Metallurgical Engineering. I am a member in good standing of the Ordre des Ingénieurs du Québec (#5018119). I have worked as a metallurgist since 2006.

 

4.I have read the definition of Qualified Person set out in the National Instrument 43-101 (Instrument) and certify that by reason of my education, affiliation with a professional association and past relevant work experiences, I fulfil the requirement to be an independent qualified person for the purposes of NI 43-101.

 

5.I have read NI 43-101 and have participated in the preparation of this Technical Report. I am responsible for Section 13 (Mineral Processing and Metallurgical Testing) excluding sections 13.2.7 and 13.3.7 and am responsible for Chapter 17 (Recovery Methods), which have been prepared in accordance with NI 43-101.

 

6.I am independent of Sigma Lithium Resources Corporation as defined by Section 1.5 of the Instrument. I do not have prior involvement with the properties that are the subject of the technical report.

 

7.As of the effective date of the Technical Report, to the best of my knowledge, information and belief, the sections of the technical report for which I am responsible contain all scientific and technical information that is required to be disclosed to make the technical report not misleading.

 

Signed and dated this 16th January 2023 at Montréal, Quebec.

 

“Signed and sealed” Jarrett Quinn

 

   
Jarrett Quinn, P.Eng. (OIQ #5018119), Ph.D., Consulting Process Engineer,  
Primero Group Americas Inc.  

 

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CERTIFICATE OF AUTHOR
PORFÍRIO CABALEIRO RODRIGUEZ

 

I, Porfirio Cabaleiro Rodriguez, FAIG., Ph.D., do hereby certify:

 

1.I am a Mining Engineer and Director for GE21 Consultoria Mineral, located at Avenida Afonso Pena, 3130 − 12º andar, Belo Horizonte, MG, Brazil, CEP 30.130-910.

 

2.This certificate applies to the Technical Report entitled “Grota do Cirilo Lithium Project, Aracuai and Itinga Regions, Minas Gerais, Brazil, Updated Technical Report.” with an effective date of 31st October 2022.

 

3.I am a graduate in Mining Engineering from the Federal University of Minas Gerais, in Belo Horizonte, Brazil. I have worked as a Mining Engineer for more than 42 years.

 

4.I am a Fellow of the Australian Institute of Geoscientists (FAIG #3708).

 

5.I have read the definition of Qualified Person set out in the National Instrument 43-101 (Instrument) and certify that by reason of my education, affiliation with a professional association and past relevant work experiences, I fulfil the requirement to be an independent qualified person for the purposes of NI 43-101.

 

6.I visited the site between 25-29 July ,2022.

 

7.I have read NI 43-101 and have participated in the preparation of this Technical Report and am responsible for Sections 15, 16, 18.4, 18.8, 19, 20, 21.1, 21.2, 21.3 and 24, and the applicable parts of 1, 25 and 26, each of which has been prepared in accordance with NI 43-101.

 

8.I am independent of Sigma Lithium Corporation as defined by Section 1.5 of the Instrument. I do not have prior involvement with the properties that are the subject of the technical report.

 

9.As of the effective date of the Technical Report, to the best of my knowledge, information and belief, the sections of the technical report for which I am responsible contain all scientific and technical information that is required to be disclosed to make the technical report not misleading.

 

Signed and dated this 16th January 2023 at Belo Horizonte, Minas Gerais State.

 

“Signed and sealed” Porfirio Cabaleiro Rodriguez, BSc. (MEng), FAIG

 

   
Porfirio Cabaleiro Rodriguez, BSc. (MEng)  
Senior Director GE21, FAIG #3708  

 

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CERTIFICATE OF AUTHOR
NOEL O’BRIEN

 

I, Noel O’Brien, FAusIMM, do hereby certify:

 

1.I am a Metallurgist and Managing Director of Trinol Pty Ltd., with a business address at 76 Stockdale Crescent, Wembley Downs, Western Australia 6009.

 

2.This certificate applies to the Technical Report entitled “Grota do Cirilo Lithium Project, Aracuai and Itinga Regions, Minas Gerais, Brazil, Updated Technical Report.” with an effective date of 31st October 2022.

 

3.I am a graduate of the University of Melbourne (BE Metallurgical Engineering) and I am a member in good standing of the AusIMM (#226758). I have worked as a metallurgical engineer since 1972.

 

4.I have read the definition of Qualified Person set out in the National Instrument 43-101 (Instrument) and certify that by reason of my education, affiliation with a professional association and past relevant work experiences, I fulfil the requirement to be an independent qualified person for the purposes of NI 43-101.

 

5.I have read NI 43-101 and have participated in the preparation of this Technical Report and am responsible for Sections 13.2.7, 13.3.7, 21 (excluding sections 21.1, 21.2 and 21.3) and 22, each of which has been prepared in accordance with NI 43-101.

 

6.I am independent of Sigma Lithium Corporation as defined by Section 1.5 of the Instrument. I do not have prior involvement with the properties that are the subject of the technical report.

 

7.As of the effective date of the Technical Report, to the best of my knowledge, information and belief, the sections of the technical report for which I am responsible contain all scientific and technical information that is required to be disclosed to make the technical report not misleading.

 

Signed and dated this 16th day of January 2023, at Wembley Downs, Western Australia.

 

“Signed and sealed” Noel O’Brien, FAusIMM

 

 
Noel O’Brien, FAusIMM  

 

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Abbreviations

 

AMIS African Mineral Standards
CAPEX Capital Expenditures
CIM Canadian Institute of Mining, Metallurgy and Petroleum
DMS Dense Medium Separation
EPCM Engineering Procurement Construction Management
FOB Free on Board
FS Feasibility Study
GE21 GE21 Mineral Consultants
HDPE High Density Polyethylene
HLS Heavy Liquid Separation
HMI Human Machine Interface
LOM Life of Mine
MEL Mechanical Equipment List
MTO Material Take-off
NPI Non-Process Infrastructure
NPV Net Present Value
OPEX Operating Expenditures
PEP Project Execution Plan
Primero Primero Group Americas Inc
Project Grota do Cirilo Lithium Project
Promon Promon Engenharia Ltda
Property Sigma Property
RFQ Request for Quotation
ROM Run of Mine
SC Spodumene Concentrate
Sigma Sigma Lithium Corporation
SGS SGS Geological Services (SGS Canada)
UCS Unconfined Compressive Strength
UPS Uninterruptible Power Supply
WBS Work Breakdown Structure

 

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1SUMMARY

 

1.1Introduction

 

Sigma Lithium Corporation (Sigma) requested SGS Geological Services (SGS) to prepare an updated NI 43-101 Technical Report (the Report) on Sigma’s Grota do Cirilo project located in Minas Gerais State, Brazil.

 

This report contains an updated Mineral Resource Estimate and the maiden Mineral Reserve Estimate for the Nezinho do Chicao pegmatite and a PFS-level study for Phase 2 & 3 of the project.

 

Sigma Mineração S.A. (SMSA) is the Brazilian subsidiary of Sigma and is the owner of the mining rights and the holder of mining concessions ordinance which includes the Xuxa, Barrerio, Murial, Lavra do Meio and Nezinho do Chicao deposits.

 

The Report supports the disclosure by Sigma in the news release dated the 5th of December 2022.

 

Mineral Resources and Mineral Reserves (MRMR) are reported using the 2014 Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Definition Standards (2014 CIM Definition Standards) and adhere to the 2019 CIM Estimation of Mineral Resources & Mineral Reserves Best Practice Guidelines (2019 CIM MRMR Guidelines).

 

1.2Property Description and Location

 

The Project is located in Northeastern Minas Gerais State, in the municipalities of Araçuaí and Itinga, approximately 25 km east of the town of Araçuaí and 450 km northeast of Belo Horizonte.

 

The Project is comprised of four properties owned by SMSA and is divided into the Northern Complex (the Grota do Cirilo, Genipapo and Santa Clara properties) and the Southern Complex (the São José property).

 

The Project consists of 27 mineral rights, which include mining concessions, applications for mining concessions and exploration permits, spread over 191 km2, and includes nine past producing lithium mines and 11 first-priority exploration targets. Granted mining concessions are in good standing with the Brazilian authorities.

 

The surface rights in the Grota do Cirilo area, the current primary focus of activity, are held by two companies, Arqueana Minérios e Metais (Arqueana) and Miazga Participações S.A. (Miazga). SMSA has entered into two right-of-way agreements with these companies to support Sigma’s exploration and development activities within the Grota do Cirilo property, as well as third-party surface owners.

 

Sigma has been issued both the Environment Provisional License and the Environment Installation License (LP&LI) and construction on Phase 1 of the project has commenced. Sigma has also been granted a Water License to pump of 150 m3/hr of water from the Jequitinhonha River for all months of the year for a period of 10 years after which the license can be renewed.

 

The Brazilian Government levies a Compensação Financeira pela Exploração de Recursos Minerais (CFEM) royalty on mineral production. Lithium production is subject to a 2.0% CFEM royalty, payable on the gross income from sales. The Project is subject to two third-party net smelter return (NSR) royalties of 1% each however, Sigma intends to exercise its option to repurchase one of the 1.0% NSRs for US$3.8 million in its first year of commercial production at the Project.

 

To the extent known to the QPs, there are no other significant factors and risks that may affect access, title, or the right or ability to perform work on the Project that have not been discussed in this Report.

 

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1.3Accessibility, Climate, Local Resources, Infrastructure and Physiography

 

The Project is easily accessible from regional paved road BR-367, which runs through the northern part of the Project. Within the Project area, accessibility is provided by a network of maintained arterial and back country service roads. A municipal airport services the town of Araçuaí. The closest major domestic airport is located at Montes Claros, 327 km west of Araçuaí.

 

The Eastern Brazil region is characterized by a dry, semi-arid and hot climate. It is expected that future mining operations could be conducted year-round. Exploration activities are year-round but can be interrupted by short-term rainfall events.

 

Mining operations have been previously conducted in the Project area. Existing infrastructure includes power supply and substation, an extensive office block equipped with internet and telephones, accommodation for 40 persons on site, dining hall and kitchen, workshop, on-site laboratory and sample storage building, warehouse and a large store, a fuel storage facility with pumping equipment, and a water pumping facility from the Jequitinhonha River with its reservoir. The main 138 kV transmission line from the Irape hydro power station runs through the northern part of the Project area. The town of Araçuaí can supply basic services. Other services must be sourced from Belo Horizonte or São Paulo.

 

The topography consists of gently rolling hills with less than 100 m difference in elevation. The Project area typically hosts thorn scrub and savannah. Much of the area has been cleared for agriculture. The primary source of water for this project is the Jequitinhonha River.

 

1.4History

 

Exploration and mining activities prior to Sigma’s project interest were conducted by Companhia Estanìfera do Brazil (CEBRAS), Arqueana Minérios e Metais (Arqueana), Tanex Resources plc (Tanex; a subsidiary of Sons of Gwalia Ltd (Sons of Gwalia)), and RI-X Mineração S.A. (RI-X). CEBRAS produced a tin/tantalite concentrate from open pit mines from 1957 to the 1980s. Arqueana operated small open pit mines from the 1980s to the 2000s, exploiting pegmatite and alluvial gravel material for tin and tantalite. Tanex Resources obtained a project interest from Arqueana, and undertook channel sampling, air-track, and reverse circulation (RC) drilling. The Project was subsequently returned to Arqueana. In 2012, RI-X obtained a controlling interest in Arqueana, and formed a new subsidiary company to Arqueana called Araçuaí Mineração whose name was later changed to SMSA. SMSA completed mapping, data compilation, a ground magnetic survey, channel sampling, and HQ core drilling. A heavy mineral separation (HMS) pilot plant was built during 2014–2015. Lithium-specific mining activities were conducted over at least five deposits in the Northern Complex, and four deposits in the Southern Complex.

 

In 2017 Sigma purchased a dense media separation (DMS) unit to produce a 6% Li2O spodumene concentrate. Sigma has completed ground reconnaissance, satellite image interpretation, geological mapping, channel and chip sampling, trenching, core drilling, Mineral Resource and Mineral Reserve estimation, and a feasibility study. Sigma initially focused on a geological assessment of available field data to prioritize the 200 known pegmatites that occur on the various properties for future evaluation. A ranking table that highlighted pegmatite volume, mineralogy and Li2O and Ta2O5 grade was established. Within the more prospective areas, Sigma concentrated its activities on detailed geological and mineralogical mapping of historically mined pegmatites, in particular, on the larger pegmatites.

 

1.5Geological Setting and Mineralization

 

The pegmatites in the Project area are classified as lithium–cesium–tantalum or LCT types. The Project area lies in the Eastern Brazilian Pegmatite Province (EBP) that encompasses a very large region of about 150,000 km2, stretching from the state of Bahia to Rio de Janeiro state.

 

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The pegmatite swarm is associated with the Neoproterozoic Araçuaí orogeny and has been divided into two main types: anatectic (directly formed from the partial melting of the country rock) or residual pegmatite (fluid rich silicate melts resulting from the fractional crystallization of a parent magma). The pegmatites in the Project area are interpreted to be residual pegmatites and are further classified as LCT types.

 

Pegmatite bodies are typically hosted in a grey biotite–quartz schist and form bodies that are generally concordant with the schist foliation but can also cross-cut foliation. The dikes are sub-horizontal to shallow-dipping sheeted tabular bodies, typically ranging in thickness from a few metres up to 40 m or more, and display a discontinuous, thin, fine-grained chilled margin. Typical pegmatite mineralogy consists of microcline, quartz, spodumene, albite and muscovite. Spodumene typically comprises about 28–30% of the dike, microcline and albite around 30–35%, and white micas about 5–7%. Locally, feldspar and spodumenes crystals can reach as much as 10–20 cm in length. Tantalite, columbite and cassiterite can occur in association with albite and quartz. The primary lithium-bearing minerals are spodumene and petalite. Spodumene can theoretically contain as much as 3.73% Li, equivalent to 8.03% Li2O, whereas petalite, can contain as much as 2.09% lithium, equivalent to 4.50% Li2O.

 

Features of the pegmatites where mineral resources have been estimated include:

 

Xuxa:

 

·foliation concordant, strikes northwest–southeast, dips to the southeast at 40º to 45º, and is not zoned. The strike length is 1,700 m, averages 12–13 m in thickness and has been drill tested to 259 m in depth. Xuxa remains open to the west, east, and at depth.

 

Barreiro:

 

·foliation discordant, strikes northeast–southwest, dips to the southeast at 30º to 35º, and is slightly zoned with a distinct spodumene zone as well as an albite zone. The pegmatite is about 600 m long (strike), 30–35 m wide, and 800 m along the dip direction. Barreiro remains open to the northeast and at depth.

 

Murial:

 

·foliation discordant, strikes north–south, and has a variable westerly dip, ranging from 25º to 75º. The strike length is about 750 m, with a thickness of 15–20 m, and the down-dip dimension is 200 m. The pegmatite is zoned with a spodumene-rich intermediate zone and a central zone that contains both spodumene and petalite. The southern section of the pegmatite has lower lithium tenors than the norther portion of the dike. Murial remains open to the north, south, and at depth.

 

Lavra do Meio:

 

·foliation concordant, strikes north–south, dips 75º–80º to the east. The strike length is 300 m with an average thickness of 12–15 m and a down-dip distance of 250 m. The pegmatite is zoned and contains both spodumene and petalite and remains open at depth.

 

Nezinho do Chicao:

 

·The pegmatite body strikes nearly north-south (020º) and dips at 40-75º to the southeast. The dike is about 1,600 m long, 200 m down-dip and 20-30 m thick. It remains open to the north, south and at depth. The NDC pegmatite is a high-grade mix of spodumene and petalite with a variable ratio depending on the thickness of the zone.

 

1.6Exploration

 

Sigma began working on the Project in June 2012, focusing on a geological assessment of available field data to prioritize the 200 known pegmatites that occur on the various properties for future evaluation. A ranking table that highlighted pegmatite volume, mineralogy and Li2O and Ta2O5 grade was established.

 

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Within the more prospective areas, Sigma concentrated its activities on detailed geological and mineralogical mapping of historically mined pegmatites, in particular, on the larger pegmatites, Xuxa and Barreiro. These dikes were channel sampled and subsequently assessed for their lithium, tantalum and cassiterite potential. This work was followed by bulk sampling, drilling and metallurgical test work. In the southern complex area, Sigma geologists have visited sites of historical workings, and undertaken reconnaissance mapping and sampling activities. The Lavra Grande, Samambaia, Ananias, Lavra do Ramom and Lavra Antiga pegmatites were mined for spodumene and heavy minerals, and in some cases gem-quality crystals were targeted. These pegmatites are considered to warrant additional work.

 

1.7Drilling

 

Drilling completed by Sigma across the Project area consists of 502 core holes totalling 96,931 m. To date, this drilling has concentrated on the Grota do Cirilo pegmatites. Drilling was completed using HQ core size (63.5 mm core diameter) in order to recover enough material for metallurgical testing. Drill spacing is variable by pegmatite, but typically was at 50 m with wider spacing at the edges of the drill pattern. Drill orientations were tailored as practicable to the strike and dip of the individual pegmatites. The drill hole intercepts range in thickness from approximately 85–95% of true width to near true width of the mineralization.

 

All core was photographed. Drill hole collars were picked up in the field using a Real Time Kinematic (RTK) global positioning system (GPS) instrument with an average accuracy of 0.01 cm. All drill holes were down-hole surveyed by Sigma personnel using the Reflex EZ-Track and Reflex Gyro instruments. Calibrations of tools were completed every year since 2017.

 

Sampling intervals were determined by the geologist, marked and tagged based on lithology and mineralization observations. The typical sampling length was 1 m but varied according to lithological contacts between the mineralized pegmatite and the host rock. In general, 1-2 m host rock samples were collected from each side that contacts the pegmatite.

 

Sigma conducted HQ drilling programs in 2014, 2017, 2018, 2020, 2021 and 2022 on selected pegmatite targets. The drill programs have used industry-standard protocols that include core logging, core photography, core recovery measurements, and collar and downhole survey measurements. There are no drilling, sampling or recovery factors that could materially impact the accuracy and reliability of the results in any of the drill campaigns. Drill results from Grota do Cirilo property support the Mineral Resource and Mineral Reserve (MRMR) estimates for the Xuxa DFS and the Barreiro/NDC PFS update.

 

1.8Sample Preparation, Analyses and Security

 

Sampling intervals were determined by the geologist, marked and tagged based on lithology and mineralization observations. The typical sampling length was 1 m but varied according to lithological contacts between the mineralized pegmatite and the host rock. In general, 1 m host rock samples were collected from each side that contacts the pegmatite.

 

All samples collected by SMSA during the 2012–2022 exploration programs were sent to the SGS Geosol laboratory (SGS Geosol) located in the city of Belo Horizonte, Brazil. A portion of the 2017–2018 and 2020-2022 sample pulps were prepared by ALS Brazil Ltda. in Vespasiano, Brazil (ALS Vespasiano) and shipped to ALS Canada Inc. Chemex Laboratory (ALS Chemex) in North Vancouver, BC, Canada for cross check validation. A portion of the 2014 samples were resampled by the QP and sent for validation to the SGS Lakefield Laboratory (SGS Lakefield) in Lakefield Canada. All laboratories, including ALS Chemex, ALS Vespasiano, SGS Lakefield and SGS Geosol are ISO/IEC 17025 accredited. The SGS Geosol laboratory is ISO 14001 and 17025 accredited by the Standards Council. All laboratories used for the technical report are independent from SMSA and Sigma and provide services to SMSA pursuant to arm’s length service contracts.

 

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Sample preparation conducted at SGS Geosol consisted of drying, crushing to 75% passing 3 mm using jaw crushers, and pulverizing to 95% passing 150 mesh (106 µm) using a ring and puck mill or a single component ring mill. In 2017, SGS Geosol performed 55-element analysis using sodium peroxide fusion followed by both inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS) finish (SGS code ICM90A). This method uses 10 g of the pulp material and returns different detection limits for each element and includes a 10 ppm lower limit detection for Li and a 10,000 ppm upper limit detection for Li. In 2018, SGS Geosol used a 31-element analytical package using sodium peroxide fusion followed by both Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) and ICP-MS finish (SGS code ICP90A). The 2020-2022 samples were assayed by SGS Geosol with a 31-element analytical package using sodium peroxide fusion followed by both Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and ICP-MS finish (SGS code ICP90A) For Li, the lower limit of detection is 10 ppm, and the upper limit of detection is 15,000 ppm (1.5% Li).

 

Sample preparation at ALS Vespasiano comprised drying, crushing to 70% passing 2 mm using jaw crushers, and pulverizing to 85% passing 200 mesh (75 µm) using a ring and puck mill or a single component ring mill. Lithium and boron were determined by sodium peroxide fusion followed by ICP-AES analysis (ALS Chemex method ME-ICP82b).

 

The 2017 witness samples collected on the 2014 drill core were analyzed at SGS Lakefield using sodium peroxide fusion followed by both ICP-OES and ICP-MS finish (SGS code ICM90A).

 

In addition to the laboratory quality assurance quality control (QA/QC) routinely implemented by SGS Geosol and ALS Chemex using pulp duplicate analysis, SMSA developed an internal QA/QC protocol for the Xuxa drilling, which consisted of the insertion of analytical standard reference materials (standards), blanks and core duplicates on a systematic basis with the samples shipped to the analytical laboratories. In 2017 and 2021, Sigma also sent pulps from selected mineralized intersections to ALS Chemex for reanalysis. No pulp reanalysis was performed by Sigma in 2013 and 2014. A total of 729 pulp samples from the 2017, 2018, 2020 and 2021 Xuxa, Barreiro, Murial and Lavra do Meio drilling programs were sent to ALS Vespasiano for third-party verification.

 

SMSA inserted standards in sample batches during the 2014, 2017–2018 and 2020-2022 sampling programs. The 2017–2018 campaign used seven certified standards from African Mineral Standards (AMIS), an international supplier of certified reference materials while the 2020-2022 campaign used four certified AMIS standards. A total of 88 standards were inserted during the 2017 campaign and 315 were inserted during the 2018 campaign, with a further 73 standards submitted in the 2021 campaign and 210 samples submitted in 2021-2022. Results were considered acceptable, and no material accuracy issues were noted.

 

During the 2017–2018 and 2020-2022 campaigns SMSA included insertion of analytical blanks in the sample series as part of their internal QA/QC protocol. The blank samples, which are made of fine silica powder provided by AMIS, are inserted an average of one for every 20 samples by the SMSA geologist and subsequently sent to SGS Geosol. The same procedure was used by SMSA for the 2014 drilling campaign. A total of 939 analytical blanks were analysed during the 2014, 2017–2018 and 2020-2022 exploration programs. Results were considered acceptable, and no material contamination issues were noted.

 

SMSA inserted coarse duplicates every 20th sample in the sample series as part of their internal QA/QC protocol. The sample duplicates correspond to a quarter HQ core from the sample left behind for reference, or a representative channel sample from the secondary channel cut parallel to the main channel. Assay results were considered acceptable between the two sample sets.

 

Bulk densities of the lithologies were measured by SGS Geosol by pycnometer measurement. Measurements were by lithology with special attention to the lithium bearing pegmatite. Separate measurements were made for the Xuxa, Barreiro, Murial, Lavra do Meio and NDC deposits.

 

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A total of 219 measurements were made on Xuxa core from 2017–2021. Of the 219 measurements, 26 were made on albite-altered pegmatite, 69 on schist, and 121 on lithium-bearing pegmatite. For Barreiro, a total of 471 measurements were made on core from the 2018 and 2021 drill programs. Of the 471 measurements, 94 were made on albite-altered pegmatite, 206 on schist, and 164 on lithium-bearing pegmatite. For Murial, a total of 134 measurements were made by the same method on core from the 2018 drill program. Of the 134 measurements, 32 were made on the albite-altered pegmatite, 58 on the schist and 44 on the lithium bearing pegmatite. For Lavra do Meio, a total of 51 measurement were made by the same method on core from the 2018 drill program. Of the 51 measurements, nine were made on the albite altered pegmatite, 22 on the schist and 20 on the lithium bearing pegmatite. For NDC, a total of 292 lithium-bearing samples had density measurements calculated, comprising 196 spodumene samples and 96 petalite samples.

 

In 2017, SGS validated the exploration processes and core sampling procedures used by SMSA as part of an independent verification program. The QP concluded that the drill core handling, logging and sampling protocols are at conventional industry standard and conform to generally accept best practices. The chain of custody was followed by SMSA employees, and the sample security procedure showed no flaws. The QP considers that the sample quality is good and that the samples are generally representative.

 

As additional QAQC, SMSA sent 664 samples from the 2017-2018 Grota do Cirillo drilling campaign to ALS Chemex for analysis using the protocol ME-ICP82b with sodium peroxide fusion. Preparation was done by ALS Vespasiano and the samples were subsequently shipped to Vancouver. The average Li concentration for the original was 6,411.4 ppm Li while the duplicate average was 6,475.9 ppm Li. This indicates a slight bias of the ALS Chemex duplicates which is well within the accepted margin of error.

 

Sigma sent 65 samples from the 2021 Barreiro drilling campaign to ALS Chemex for check sample analysis using the ALS Chemex protocol ME-ICP82b with sodium peroxide fusion.

 

The average lithium concentration for the original samples was 6,518.0 ppm Li and the duplicates averaged 6,559.7 ppm Li, with an average difference of 41.7 ppm or 0.6%. The correlation coefficient R2 of 0.9854 suggests a strong correlation and a high similarity between the two sets of samples.

 

Sigma sent 304 samples from the 2021-2022 NDC drilling campaign to ALS Chemex for check sample analysis using the ALS Chemex protocol ME-ICP82b with sodium peroxide fusion.

 

The average lithium grade for the original samples was 1.38% Li2O and the duplicates averaged 1.39% Li2O. The correlation coefficient R2 of 0.98 suggests a strong correlation and a high similarity between the two sets of samples.

 

A total of 216 coarse duplicates and 216 pulp duplicates from NDC were submitted for analysis from the 2021 and 2022 drill programs. For the coarse duplicates, the average of the original samples was 1.44% Li2O, while the duplicates averaged 1.42% Li2O, while the original pulp samples averaged 1.43% Li2O, with the pulp duplicates also averaging 1.43% Li2O.

 

Overall, the QP is confident that the system is appropriate for the collection of data suitable for a Mineral Resource estimate and can support Mineral Reserve estimates and mine planning.

 

1.9Data Verification

 

Visits to the Project site were conducted by Marc-Antoine Laporte, P.Geo., M.Sc. from September 11 to September 15, 2017, from July 11 to July 17, 2018, from September 18 to 23, 2018, from October 18 to 21, 2021 and from May 30 to June 1, 2022. These visits enabled the QP to become familiar with the exploration methods used by SMSA, the field conditions, the position of the drill hole collars, the core storage and logging facilities and the different exploration targets.

 

The database for the Project was transmitted to SGS by Sigma as comma separated values (csv) files and regularly updated by Sigma geologists. The database contains data for: collar locations; downhole surveys; lithologies and lithium assays. Upon importation of the data into the SGS proprietary modelling and mineral resources estimation software (Genesis©), SGS conducted a second phase of data validation where any discrepancies were identified and removed from the database, after consultation and verification with Sigma geologists. Finally, SGS conducted random checks on approximately 5% of the assay certificates, to validate the assay values entered in the database.

 

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Witness sampling was undertaken in 2017 on previously sampled mineralized intervals, with the remaining half core cut to quarter core, and the samples submitted to the SGS Lakefield lab for analysis. A total of nine mineralized intervals were sampled to compare the average grade for the two different laboratories. The average for the original samples is 1.61 % Li2O while the average for the control samples is 1.59 % Li2O. The average grade difference is 0.02% which makes a relative difference of 1.28% between the original and the control samples.

 

Following the data verification process and QA/QC review, the QP is of the opinion that the sample preparation, analysis and QA/QC protocol used by SMSA for the Project follow generally accepted industry standards and that the Project data is of a sufficient quality.

 

1.10Mineral Processing and Metallurgical Testing

 

1.10.1Xuxa

 

Drill core samples from the Xuxa pegmatite deposit were processed at the SGS Lakefield facility in 2018 and 2022, samples from Barreiro were tested between November 2020 and May 2021, and samples from Nezinho do Chicao in 2022. Work conducted on the Xuxa samples included comminution, heavy liquid separation (HLS), REFLUX™ classifier, dense media separation (DMS) and magnetic separation. The Barreiro test work program included sample characterization, grindability testing, HLS and DMS metallurgical test work. The Nezinho do Chicao test work program included sample characterization, mineralogical analyses, HLS, DMS, and magnetic separation. Xuxa

 

Drill core samples were selected and combined into six variability (Var) samples for a test work program comprising of mineralogical analyses, grindability, HLS, REFLUX™ classifier, DMS, and magnetic separation testing. Flowsheets for lithium beneficiation were developed in conjunction with the test work. The goal was to produce spodumene concentrate grading a minimum 6% Li2O and maximum 1% Fe2O3 while maximizing lithium recovery.

 

Four HLS tests, at four crush sizes (15.9 mm, 12.5 mm, 9.5 mm, and 6.3 mm) were carried out on each of the six variability samples to evaluate the recovery. The 9.5 mm crush size was selected as the optimum crush size for DMS test work, as it resulted in the highest lithium recovery with minimal fines generation.

 

The DMS variability samples were each crushed to -9.5 mm and screened into four size fractions: coarse (-9.5 mm/+6.3 mm), fines (-6.3 mm/+1.7 mm), ultrafines (-1.7 mm/+0.5 mm) and hypofines (-0.5 mm). The coarse, fines and ultrafines fractions of each variability sample were processed separately for lithium beneficiation. The REFLUX™ classifier (RC) test work was carried out with a RC-100 unit for mica rejection from the fines and ultrafines fractions only. This test work was conducted at FLSmidth’s Minerals Testing and Research Center in Utah, USA.

 

The coarse, fines and ultrafines RC underflow streams of each variability sample were processed separately through DMS. The DMS concentrate from each fraction underwent dry magnetic separation at 10,000 gauss.

 

The DMS test work flowsheet for the coarse and fines fractions included two passes through the DMS; the first at a lower specific gravity (SG) cut-point (~2.65) to reject silicate gangue and the second pass at a higher SG cut-point (ca. ~2.90) to generate spodumene concentrate. The coarse DMS middlings were re-crushed to -3.3 mm and a two stage HLS test was conducted. The ultrafines DMS test work flowsheet included both a single pass and a double pass DMS circuit at a high SG cut-point (~2.90) to generate spodumene concentrate.

 

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The DMS test results demonstrated the ability to produce spodumene concentrate with >6% Li2O in most of the tests. Based on the test work results, a lithium recovery of 60.4% was selected for plant design.

 

1.10.2Barreiro

 

Four variability and one composite sample were tested for Barreiro, with the goals of the program to provide preliminary process information on the metallurgical performance of mineralized material from the Barreiro deposit. The test work program was developed based on the flowsheet developed for the Xuxa deposit. The aim of the test work program was to produce chemical grade spodumene concentrate (>6% Li2O) with low iron content (<1% Fe2O3), while maximizing lithium recovery.

 

Two sets of HLS tests were undertaken. The first set was conducted using the Composite to test optimal crush size (i.e., top size of 15.9 mm, 12.5 mm, 10.0 mm, and 6.3 mm). HLS tests were then performed on each variability sample at the optimum crush size. The fine fraction (i.e., -0.5 mm) was screened out from each sub-sample and the oversize fraction was submitted for HLS testing. A crush size of -10 mm was determined to be optimal and variability HLS testing was undertaken at this crush size. Interpolated stage recoveries (6% Li2O concentrate) for the four variability samples ranged from 56.0% to 77.3%.

 

In all four variability samples, HLS tests produced >6% Li2O spodumene concentrate with low iron content (<1.0% Fe2O3).

 

Pilot-scale DMS test work was operated on the composite sample. Dry magnetic separation was undertaken on the DMS feed. DMS test work results showed combined spodumene concentrate grade of 6.11% Li2O and stage recovery of 59.5% for a global recovery of 50.9%.

 

1.10.3Nezinho do Chicao

 

Three variability samples and one composite sample were tested for Nezinho do Chicao (NDC), with the goal of the program to provide process information on the metallurgical performance of mineralized material from the NDC deposit. The test work program was developed based on the flowsheet developed for the Barreiro deposit. The aim of the test work program was to produce chemical grade spodumene concentrate (>5.5% Li2O) with low iron content (<1% Fe2O3), while maximizing lithium recovery.

 

HLS tests were undertaken across four different crush sizes (i.e., top size of 15.9 mm, 12.5 mm, 9.5 mm, and 6.3 mm) to determine the optimum crush size, for each ore (high grade, medium grade and low grade). The fine fraction (i.e., -0.5 mm) was screened out from each sub-sample and the oversize fraction was submitted for HLS testing. A crush size of -9.5mm was determined to be optimal and variability HLS testing was undertaken at this crush size. Interpolated stage recoveries (5.5% Li2O concentrate) for the three variability samples ranged from 58.7% to 61.4%, and the master composite a nominal 57.8%, for the 9.5mm crushed process step 1.54% Li2O head grade.

 

Pilot-scale DMS test work was operated on the composite sample. Dry magnetic separation was undertaken on the DMS feed. DMS test work results showed combined spodumene concentrate grade with petalite 5.50% Li2O and stage recovery of 58.7% for a global recovery of 50.6%.

 

1.11Mineral Resource Estimates

 

Mineral Resources for the Grota do Cirilo pegmatite were estimated using a computerised resource block model. Three-dimensional wireframe solids of the mineralisation were defined using drill hole Li2O analytical data.

 

Data were composited to 1 m composite lengths, based on the north–south width of the block size defined for the resource block model. Compositing starts at the schist-pegmatite contact. No capping was applied on the analytical composite data. The Xuxa, Murial, Lavra do Meio and NDC models used a 5 m x 3 m x 5 m block size and the Barreiro model used a 5 m x 5 m x 5 m block. Average densities were applied to blocks, which varied by pegmatite, from 2.65 t/m3 at Lavra do Meio to 2.71 t/m3 at Barreiro.

 

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Variography was undertaken for Xuxa, Barreiro, Lavra do Meio and NDC, and the projection and Z-axis rescaling were done according to the mineralization orientation.

 

The grade interpolation for the Xuxa, Barreiro, Lavra do Meio, and NDC resource block models were completed using ordinary kriging (OK). The Murial model was estimated using an inverse distance weighting to the second power (ID2) methodology. The interpolation process was conducted using three successive passes with more inclusive search conditions from the first pass to the next until most blocks were interpolated, as follows:

 

Pass 1:

 

·Xuxa: search ellipsoid distance of 75 m (long axis) by 75 m (intermediate axis) and 25 m (short axis) with an orientation of 130° azimuth and -50° dip to the southeast; minimum of seven composites, a maximum of 15 composites and a minimum of three drill holes.

·Barreiro: search ellipsoid distance of 55 m (long axis) by 55 m (intermediate axis) and 25 m (short axis) with an orientation of 155° azimuth and -35° dip to the southeast; a minimum of seven composites, a maximum of 15 composites and a minimum of three drill holes.

·Murial: 75 m (long axis) by 75 m (intermediate axis) and 35 m (short axis) with an orientation of 95° azimuth and -80° dip to the west; minimum of seven composites, a maximum of 15 composites and a minimum of three drill holes.

·Lavra do Meio: 50 m (long axis) by 50 m (intermediate axis) and 25 m (short axis) with an orientation of 280° azimuth and -75° dip to the east; minimum of five composites, a maximum of 15 composites and a minimum of three drill holes.

·NDC: search ellipsoid distance of 75 m (long axis) by 75 m (intermediate axis) and 25 m (short axis) with an orientation of 18° azimuth and -50° dip to the east; minimum of seven composites, a maximum of 15 composites and a minimum of three drill holes.

 

Pass 2:

 

·Xuxa: twice the search distance of the first pass; minimum of seven composites, a maximum of 15 composites and a minimum of three drill holes.

·Barreiro: twice the search distance of the first pass; a minimum of seven composites, a maximum of 15 composites and a minimum of three drill holes.

·Murial: twice the search distance of the first pass; minimum of seven composites, a maximum of 15 composites and a minimum of three drill holes.

·Lavra do Meio: twice the search distance of the first pass; minimum of five composites, a maximum of 15 composites and a minimum of three drill holes.

·NDC: twice the search distance of the first pass; minimum of seven composites, a maximum of 15 composites and a minimum of three drill holes.

 

Pass 3:

 

·Xuxa: 300 m (long axis) by 300 m (intermediate axis) by 100 m (short axis) with a minimum of seven composites, a maximum of 25 composites and a minimum of three drill holes.

·Barreiro: 250 m (long axis) by 250 m (intermediate axis) by 100 m (short axis) with a minimum of seven composites, a maximum of 25 composites and no minimum number of drill holes.

·Murial: 200 m (long axis) by 200 m (intermediate axis) by 100 m (short axis) with a minimum of seven composites, a maximum of 20 composites and no minimum number of drill holes.

·Lavra do Meio: 125 m (long axis) by 125 m (intermediate axis) by 75 m (short axis) with a minimum of five composites, a maximum of 15 composites and no minimum composites required per drill hole.

·NDC: 300 m (long axis) by 300 m (intermediate axis) by 100 m (short axis) with a minimum of seven composites, a maximum of 25 composites and a minimum of three drill holes.

 

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The estimates and models were validated by statistically comparing block model grades to the assay and composite grades, and by comparing block values to the composite values located inside the interpolated blocks. The estimates were considered reasonable.

 

Mineral Resources are classified into Measured, Indicated and Inferred categories. The Mineral Resource classification is based on the density of analytical information, the grade variability and spatial continuity of mineralization. The Mineral Resources were classified in two successive stages: automated classification, followed by manual editing of final classification results. Classifications were based on the following:

 

Measured Mineral Resources

 

·Xuxa: the search ellipsoid used was 50 m (strike) by 50 m (dip) by 25 m with a minimum of seven composites in at least three different drill holes.

·Barreiro, Murial, and Lavra do Meio: the search ellipsoid was 55 m (strike) by 55 m (dip) by 35 m with a minimum of five composites in at least three different drill holes

·NDC: the search ellipsoid used was 75 m (strike) by 75 m (dip) by 25 m with a minimum of seven composites in at least three different drill holes.

 

Indicated Mineral Resources.

 

·In all deposits, the search ellipsoid was twice the size of the Measured category ellipsoid using the same composites selection criteria.

 

Inferred Mineral Resources

 

·In all deposits, all remaining blocks.

 

Conceptual economic parameters were used to assess the reasonable prospects of eventual economic extraction. A series of economic parameters were estimated to represent the production cost and economic prospectivity of an open pit mining operation in Brazil and came either from SGS Canada or SMSA. These parameters are believed to be sufficient to include all block models in future open pit mine planning, due mostly to the relatively low mining costs in Brazil.

 

The Mineral Resource estimates for Grota do Cirilo are reported in Table 1-1 to Table 1-5 using a 0.5% Li2O cut-off. The Mineral Resource estimates are constrained by the topography and are based on the conceptual economic parameters. The Xuxa, Murial and Lavra do Meio estimates have an effective date of January 10, 2019, the Barreiro estimate has an effective date of February 10, 2022, and the NDC estimate has an effective date of October 31, 2022. The QP for the estimates is Mr. Marc-Antoine Laporte, P.Geo., an SGS employee.

 

Table 1-1: NDC Deposit Mineral Resource Estimate

 

Cut-off Grade
Li2O (%)
Category Tonnes
(Mt)
Average
Grade Li2O
(%)
Contained
LCE (Kt)
0.5 Measured 2.4 1.56 93
0.5 Indicated 24.3 1.48 889
0.5 Measured + Indicated 26.7 1.49 984

 

Notes to accompany Table 1-1 NDC Mineral Resource Estimate:

 

1.Mineral Resources have an effective date of October 31, 2022 and have been classified using the 2014 CIM Definition Standards. The Qualified Person for the estimate is Mr. Marc-Antoine Laporte, P.Geo., an SGS employee.

2.All Resources are presented undiluted and in situ, constrained by continuous 3D wireframe models, and are considered to have reasonable prospects for eventual economic extraction.

3.Mineral Resources are reported assuming open pit mining methods, and the following assumptions: lithium concentrate (6% Li2O) price of US$1,500/t, mining costs of US$2.2/t for mineralization and waste, crushing and processing costs of US$10/t, general and administrative (G&A) costs of US$4/t, concentrate recovery of 60%, 2% royalty payment, pit slope angles of 52-55º, and an overall cut-off grade of 0.5% Li2O.

4.Tonnages and grades have been rounded in accordance with reporting guidelines. Totals may not sum due to rounding.

 

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5.Mineral resources which are not mineral reserves do not have demonstrated economic viability. An Inferred Mineral Resource has a lower level of confidence than that applying to a Measured and Indicated Mineral Resource and must not be converted to a Mineral Reserve. It is reasonably expected that the majority of Inferred Mineral Resources could be upgraded to Indicated Mineral Resources with continued exploration.

6.The results from the pit optimization are used solely for the purpose of testing the “reasonable prospects for economic extraction” by an open pit and do not represent an attempt to estimate mineral reserves. There are no mineral reserves on the Property. The results are used as a guide to assist in the preparation of a Mineral Resource statement and to select an appropriate resource reporting cut-off grade.

7.The estimate of Mineral Resources may be materially affected by environmental, permitting, legal, title, taxation, socio-political, marketing, or other relevant issues.

 

Table 1-2: Xuxa Deposit Mineral Resource Estimate

 

Cut-off Grade
Li2O (%)
Category Tonnage
(t)
Average Grade
Li2O (%)
LCE (Kt)
0.5 Measured 10,193,000 1.59 400.8
0.5 Indicated 7,221,000 1.49 266.1
0.5 Measured + Indicated 17,414,000 1.55 666.9
0.5 Inferred 3,802,000 1.58 148.6

 

Notes to accompany Table 1.2 Xuxa Deposit Mineral Resource Estimate:

 

1.Mineral Resources have an effective date of January 10, 2019 and have been classified using the 2014 CIM Definition Standards. The Qualified Person for the estimate is Mr. Marc-Antoine Laporte, P.Geo., an SGS employee.

2.Mineral Resources are reported assuming open pit mining methods, and the following assumptions: lithium concentrate (6% Li2O) price of US$1,000/t, mining costs of US$2/t for mineralization and waste, US$1.2/t for overburden, crushing and processing costs of US$12/t, general and administrative (G&A) costs of US$4/t, concentrate recovery of 85%, 2% royalty payment, pit slope angles of 55º, and an overall cut-off grade of 0.5% Li2O.

3.Tonnages and grades have been rounded in accordance with reporting guidelines. Totals may not sum due to rounding.

4.Mineral Resources are reported inclusive of those Mineral Resources converted to Mineral Reserves. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.

 

Table 1-3: Barreiro Deposit Mineral Resource Estimate

 

Cut-off Grade
Li2O (%)
Category Tonnage
(t)
Average
Grade Li2O
(%)
LCE (Kt)
0.5 Measured 18,741,000 1.41 653.5
0.5 Indicated 6,341,000 1.30 203.9
0.5 Measured + Indicated 25,081,000 1.38 857.4
0.5 Inferred 3,825,000 1.39 131.5

 

Notes to accompany Table 1-3 Barreiro Deposit Mineral Resource table:

 

1.Mineral Resources have an effective date of February 11, 2022 and have been classified using the 2014 CIM Definition Standards. The Qualified Person for the estimate is Mr. Marc-Antoine Laporte, P.Geo., an SGS employee.

2.All Resources are presented undiluted and in situ, constrained by continuous 3D wireframe models, and are considered to have reasonable prospects for eventual economic extraction.

3.Mineral Resources are reported assuming open pit mining methods, and the following assumptions: lithium concentrate (6% Li2O) price of US$1,500/t, mining costs of US$2.2/t for mineralization and waste, crushing and processing costs of US$10/t, general and administrative (G&A) costs of US$4/t, concentrate recovery of 60.7%, 2% royalty payment, pit slope angles of 52-55º, and an overall cut-off grade of 0.5% Li2O.

4.Tonnages and grades have been rounded in accordance with reporting guidelines. Totals may not sum due to rounding.

5.Mineral resources which are not mineral reserves do not have demonstrated economic viability. An Inferred Mineral Resource has a lower level of confidence than that applying to a Measured and Indicated Mineral Resource and must not be converted to a Mineral Reserve. It is reasonably expected that the majority of Inferred Mineral Resources could be upgraded to Indicated Mineral Resources with continued exploration.

 

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6.The results from the pit optimization are used solely for the purpose of testing the “reasonable prospects for economic extraction” by an open pit and do not represent an attempt to estimate mineral reserves. There are no mineral reserves on the Property. The results are used as a guide to assist in the preparation of a Mineral Resource statement and to select an appropriate resource reporting cut-off grade.

7.The estimate of Mineral Resources may be materially affected by environmental, permitting, legal, title, taxation, socio-political, marketing, or other relevant issues.

 

Table 1-4: Murial Deposit Mineral Resource Estimate

 

Cut-off Grade
Li2O (%)
Category Tonnage
(t)
Average
Grade Li2O
(%)
LCE (Kt)
0.5 Measured 4,175,000 1.17 120.8
0.5 Indicated 1,389,000 1.04 35.7
0.5 Measured + Indicated 5,564,000 1.14 156.5
0.5 Inferred 669,000 1.06 17.5

 

Notes to accompany Table 1.4 Murial Deposit Mineral Resource Estimate

 

1.Mineral Resources have an effective date of January 10, 2019 and have been classified using the 2014 CIM Definition Standards. The Qualified Person for the estimate is Mr. Marc-Antoine Laporte, P.Geo., an SGS employee.

2.Mineral Resources are reported assuming open pit mining methods, and the following assumptions: lithium concentrate (6% Li2O) price of US$1,000/t, mining costs of US$2/t for mineralization and waste, US$1.2/t for overburden, crushing and processing costs of US$12/t, general and administrative (G&A) costs of US$4/t, concentrate recovery of 85%, 2% royalty payment, pit slope angles of 55º, and an overall cut-off grade of 0.5% Li2O.

3.Tonnages and grades have been rounded in accordance with reporting guidelines. Totals may not sum due to rounding.

4.Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability

 

Table 1-5: Lavra do Meio Deposit Mineral Resource Estimate

 

Cut-off

Grade Li2O

(%)

Category Tonnage
(t)
Average
Grade Li2O
(%)
LCE (Kt)
0.5 Measured 1,626,000 1.16 44.6
0.5 Indicated 649,000 0.93 14.9
0.5 Measured + Indicated 2,275,000 1.09 59.5
0.5 Inferred 261,000 0.87 5.6

 

Notes to accompany Table 1.5 Lavra do Meio Deposit Mineral Resource Estimate

 

1.Mineral Resources have an effective date of January 10, 2019 and have been classified using the 2014 CIM Definition Standards. The Qualified Person for the estimate is Mr. Marc-Antoine Laporte, P.Geo., an SGS employee.

2.Mineral Resources are reported assuming open pit mining methods, and the following assumptions: lithium concentrate (6% Li2O) price of US$1,000/t, mining costs of US$2/t for mineralization and waste, US$1.2/t for overburden, crushing and processing costs of US$12/t, general and administrative (G&A) costs of US$4/t, concentrate recovery of 85%, 2% royalty payment, pit slope angles of 55º, and an overall cut-off grade of 0.5% Li2O.

3.Tonnages and grades have been rounded in accordance with reporting guidelines. Totals may not sum due to rounding.

4.Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.

 

Factors that can affect Grota do Cirilo Mineral Resource estimates include but are not limited to:

 

·Changes to the modelling method or approach.

·Changes to geotechnical assumptions, in particular, the pit slope angles.

·Metallurgical recovery assumption that are based on preliminary test results.

 

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·Changes to any of the social, political, economic, permitting, and environmental assumptions considered when evaluating reasonable prospects for eventual economic extraction.

·Mineral Resource estimates can also be affected by the market value of lithium and lithium compounds.

 

1.12Mineral Reserve Estimates

 

1.12.1Xuxa Mineral Reserves

 

Xuxa Mineral Reserve estimates have an effective date of 26th of June 2021 and have been converted from Measured and Indicated Mineral Resources. The key parameters upon which the 26 June 2021 Mineral Reserve estimates were defined are summarized in Table 1-6.

 

Table 1-6: Parameters Used in Xuxa Pit Optimization

 

Item Unit Value
Revenue Sales Price US$/t conc.* $1500.00
Ore Density g/cm³ fixed in model
Grade % Li2O fixed in model
Mining Mine Recovering % fixed in model
Dilution fixed in model
Block Model Dimensions Block Dimensions Unit value
X x Y x Z m 5 x 3 x 5
General Angle Soil º 34
Saprolite 37.5
Fresh Rock

Sector 1 – 72º

 

Sector 2 – 50º

 

Processing Metallurgical Recovery** % 60.7
Mass Recovery*** % Calculated in block
Concentrated Grade % Li2O 6.0
Cut-off % Li2O 0.5
Costs Mining US$/t mined $2.20
Processing US$/t ore $10.70
G&A (Adjusted for OPEX) $4.00
Sale (2% cost of sale) US$/t product $14.66
  Royalties (CFEM 2%) $14.66

 

Note: * conc. = concentrate, ** based on DMS Tests, *** Including 15% fines losses - FOB Mine

 

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Proven and Probable Mineral Reserves are as presented in Table 1-7.

 

Table 1-7: Xuxa Mineral Reserves

 

Sigma FS Xuxa

5 x 3 x 5 (m) Block Dimensions

97% Mine Recovery, 3.75% Dilution

(Effective date: 6/26/2021)

Classification Tonnage (Mt) Li2O(%) LCE(Kt)
Proven 8.34 1.55 319.7
Probable 3.46 1.54 131.8
Total 11.80 1.55 451.5

 

Notes to accompany Mineral Reserves table:

 

1.Mineral Reserves were estimated using Geovia Whittle 4.3 software and following the economic parameters listed below:

2.Sale price for Lithium concentrate at 6% Li2O = US$1,500/t concentrate FOB Mine

3.Exchange rate US$1.00 = R$5.00.

4.Mining costs: US$2.20/t mined.

5.Processing costs: US$10.7/t ore milled.

6.G&A: US$4.00/t ROM (run of mine).

7.Mineral Reserves are the economic portion of the Measured and Indicated Mineral Resources.

8.97% Mining Recovery and 3.75% Mining Dilution

9.Final slope angle: 34° to 72° based on Geotechnical Document presented in Section 16.

10.Inferred Mineral Resources with the Final Operational Pit is 0.68 Mt grading at 1.52% Li2O. The Inferred Mineral Resources are not included in the Mineral Reserves.

11.Strip Ratio = 16.6 t/t (waste+Inferred mineral resources)/mineral reserves.

12.The Qualified Person for the estimate is Porfírio Cabaleiro Rodriguez, BSc. (MEng), FAIG, an employee of GE21..

 

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1.12.2Barreiro Mineral Reserves

 

The Barreiro Mineral Reserve estimates have an effective date of February 24, 2022 and have been converted from Measured and Indicated Mineral Resources. The key parameters upon which the February 24, 2022 Mineral Reserve estimates were defined are summarized in Table 1-8.

 

Table 1-8: Parameters Used in Barreiro Pit Optimization

 

Item Unit Value
Revenue Sales Price US$/t conc.* $1,500
Ore Density g/cm³ Block model
Grade % Li2O Block model
Mining Mine Recovering % Block model
Dilution Block model
Block Model Dimensions Block Dimensions Unit value
X x Y x Z m 5 x 5 x 5
General Angle Overburden º

Sector 1 – 35º

 

Sector 2 – 37º

Fresh Rock

Sector 1 – 55º

 

Sector 2 – 52º

Processing Metallurgical Recovery** % 60.0
Mass Recovery*** % Calculated in block
Concentrated Grade % Li2O 6.0
Cut-off % Li2O 0.5
Costs Mining US$/t mined $2.19 (Ore)/$1.88 (Waste)
Processing US$/t ore $10.70
G&A (Adjusted for OPEX) $4.00
Sale (2% cost of sale) US$/t product $14.66
  Royalties (CFEM 2%) $14.66

 

Note: * conc. = concentrate, ** based on DMS Tests, *** Including 15% fines losses - FOB Mine

 

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Proven and Probable Mineral Reserves are as presented in Table 1-9.

 

Table 1-9: Barreiro Mineral Reserves

 

Sigma PFS Barreiro

5 x 5 x 5 (m) Block Dimensions

97% Mine Recovery, 3.00% Dilution

(Effective date: 2/24/2022)

Classification Tonnage (Mt) Li2O(%) LCE(Kt)
Proven 16.93 1.38 576.8
Probable 4.83 1.29 153.1
Total 21.76 1.36 729.9

 

Notes to accompany Mineral Reserves table:

 

1.Mineral Reserves were estimated using Geovia Whittle 4.3 software and following the economic parameters listed below:

2.Sale price for Lithium concentrate at 6% Li2O = US$1,500/t concentrate FOB Mine.

3.Exchange rate US$1.00 = R$5.00.

4.Mining costs: US$2.19/t mined.

5.Processing costs: US$10.7/t ore milled.

6.G&A: US$4.00/t ROM (run of mine).

7.Mineral Reserves are the economic portion of the Measured and Indicated Mineral Resources.

8.97% Mine Recovery and 3% Mine Dilution

9.Final slope angle: 35° to 55° based on Geotechnical Document presented in Section 16.

10.Inferred Mineral Resources with the Final Operational Pit is 0.59 Mt grading at 1.32% Li2O. The Inferred Mineral Resources are not included in the Mineral Reserves.

11.Strip Ratio = 12.5 t/t (waste+Inferred mineral resource)/mineral reserve.

12.The Qualified Person for the estimate is Porfírio Cabaleiro Rodriguez, BSc. (MEng), FAIG, an employee of GE21.

 

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1.12.3Nezinho do Chicao Mineral Reserves

 

Nezinho do Chicao (NDC) Mineral Reserve estimates have an effective date of 31st October 2022 and have been converted from Measured and Indicated Mineral Resources, as prepared by SGS Geological Services (SGS Canada). The key parameters upon which the Mineral Reserve estimates were defined are summarized in Table 1-10.

 

Table 1-10: Parameters Used in NDC Pit Optimization

 

Item Unit Value
Revenue Financial Parameters Sales Price US$/t conc 3500
Discount rate % 10
ROM Density g/cm³ model
Grades % Li2O model
Mining Mining Recovery % model
Dilution model
Block Model Block dimensions Unit Value
X m 5
Y 3
Z 5
Overall Slope Angle Overburden º 35
Fresh Rock 52
Processing Metallurgical Recovery DMS** % 60.7
Mass Recovery % Calculated for each block
Concentrate Grade % Li2O 6
Cut-off Grade (fixed by program) % Li2O 0.5
Costs Mining US$/t mined 2.43
Processing US$/t ROM 10.7
G&A 4
Sales (2% sales cost) US$/t product 14.66
  Royalties (CFEM 2%) 14.66

 

Note: * conc. = concentrate, ** based on DMS Tests, *** Including 15% fines losses - FOB Mine

 

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Proven and Probable Mineral Reserves are as presented in Table 1-11.

 

Table 1-11: Nezinho do Chicao Mineral Reserves

 

Sigma PFS Nezinho do Chicão

5 x 3 x 5 (m) Block Dimensions

94% Mine Recovery, 3% Dilution

(Effective date: 10/30/2022)

Classification Tonnage (Mt) Li2O(%) LCE(Kt)*
Proven 2.17 1.53 82.1
Probable 19,02 1.44 677.3
Total 21.19 1.45 759.4

 

*Lithium Carbonate Equivalent

 

Notes to accompany Mineral Reserves table:

 

1.Mineral Reserves were estimated using Geovia Whittle 4.3 software and following the economic parameters listed below:

2.Sale price for Lithium concentrate at 6% Li2O = US$3,500/t concentrate FOB Mine.

3.Mining costs: US$2.43/t mined.

4.Processing costs: US$10.7/t ore milled.

5.G&A: US$4.00/t ROM (run of mine).

6.Exchange rate US$1.00 = R$5.30.

7.Mineral Reserves are the economic portion of the Measured and Indicated Mineral Resources.

8.94% Mine Recovery and 3% Mine Dilution

9.Final slope angle: 35° to 52° based on Geotechnical Study conducted by Itaaçu.

10.Strip Ratio = 16.01 t/t (waste)/mineral reserve.

11.The Competent Person for the estimate is Porfírio Cabaleiro Rodriguez, BSc. (MEng), FAIG, an employee of GE21.

 

1.13Mining Methods

 

Sigma has undertaken a program of resource drilling for the Xuxa, Barreiro and NDC deposits. Most drill holes have been geotechnically logged for structural data. The geotechnical data logged from these holes has been analyzed to provide estimates of slope stability, using industry standard empirical techniques.

 

1.13.1Xuxa

 

The mine layout and operation are based on the following criteria:

 

·Two independent open pits areas: Pit 1 in the north and Pit 2 in the south

·Single access from both pits to the mine infrastructure pad and the processing plant

·Pit wall pre-splitting of the ore zone to reduce mine dilution

·Elevated inter-ramp angles for the waste to reduce strip ratio.

 

The basis for the scheduling includes:

 

·Six months of pre-stripping to liberate the ore

·Pit 1 and Pit 2 mined in conjunction from Year 1 to Year 8 to reduce the drop-down rate and to facilitate the 1.5 Mtpa production rate

·The planned open pit mine life is eight years

·The mining fleet is based on road trucks operated by a mining contractor.

 

1.13.2Barreiro

 

The mine layout and operation are based on the following criteria:

 

·A single open pit on the Barreiro pegmatite

·Low height mineralized material benches to reduce mine dilution and maximize mine recovery

·Pre-splitting of the mineralized material to reduce mine dilution

·Elevated inter-ramp angles for the waste to reduce strip ratio

 

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The basis for the scheduling includes:

 

·Pit wall pre-stripping the pit to liberate mineralized material

·Pit push-backs in years 4 to 6 to expand and allow deepening of the pit

·Mining at a rate of 1.80 Mtpa

·The planned open pit mine life is 12 years

·The mining fleet is based on road trucks operated by a mining contractor.

 

1.13.3Nezinho do Chicao

 

The mine layout and operation are based on the following criteria:

 

·Two independent open pits areas: Pit 1 in the north and Pit 2 in the south

·Low height mineralized material benches to reduce mine dilution and maximize mine recovery

·Pit wall pre-splitting of the mineralized material to reduce mine dilution

·Elevated inter-ramp angles for the waste to reduce strip ratio

 

The basis for the scheduling includes:

 

·Mining at a rate of 1.80 Mtpa

·The planned open pit mine life is 12 years

 

The mining fleet is based on road trucks operated by a mining contractor.

 

1.14RECOVERY Methods

 

The Xuxa concentrator plant is designed to produce a target 6.0% Li2O spodumene concentrate from an ore grade of 1.46% Li2O (diluted) using dense media separation (DMS).

 

A second DMS concentrator plant would be constructed to process Barreiro ore. This plant would produce a minimum 6.0% Li2O spodumene concentrate from an ore grade of 1.39% Li2O (diluted).

 

With the integration and proposed new development of the NDC mine, the wholistic mining strategy and operational strategy will be designed around a combined Phase 2 & 3 process facility.

 

Compared to Xuxa and Barreiro ores, the NDC ore does not respond as well due to different lithium deportment and mineralogy, so when processed the target concentrate grade drops to a nominal 5.5% contained lithium concentrate as spodumene and petalite from an ore grade of 1.44% Li2O (diluted).

 

1.14.1Processing Plant Description

 

The Xuxa plant (Phase 1) throughput capacity is based on 1.7 Mtpa (dry) of ore fed to the crushing circuit, while the Barreiro plant (Phase 2) is based on a nominal 1.85 Mtpa throughput capacity. The Barreiro and NDC Plant (Phase 2&3) with have a capacity of 3.9Mtpa.

 

All three concentrator plants are designed based on a proven DMS circuit and include conventional three-stage crushing and screen circuit, up-flow classification for mica removal, two-stage coarse DMS circuit, two-stage fines DMS circuit, two-stage ultrafines circuit, as well as magnetic separation on the fines and ultrafines DMS concentrate final product streams.

 

When NDC ore is treated through the Phase 2 &3 process facility, a third DMS circuit is proposed, to recover additional lithium units as petalite from the spodumene DMS float stream. The sinks from this circuit reports to the tailings, while the floats (petalite) report to the spodumene stockpile.

 

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Front-End Engineering Design (FEED) was completed for the Xuxa concentrator. Xuxa design data is based on feasibility-level metallurgical test work conducted at SGS Canada Inc. in Lakefield, Ontario. The mass balance, process design criteria and process flow diagrams were developed based on these test work data.

 

Design of the combined Barreiro and NDC concentrator is based on PFS-level test work conducted by SGS Canada Inc. in Lakefield, Ontario.

 

1.14.2Design Criteria and Utilities Requirements

 

The utilities consumption requirements for each plant are approximately 6.7 MW for the process plant and 1.5 MW for non-process infrastructure at the process plant.

 

The Phase 1 raw water consumption for process water is nominal a 35 m3/hr (make-up raw water requirement).

 

The process water will be recycled within the plant using a thickener, where all fines slurry streams will be directed and recovered. This water will be pumped to the process water tank and recycled to the circuits.

 

Consumables will include reagents and operational consumables for the crushing circuit and the DMS plant.

 

1.15Project Infrastructure

 

The Xuxa project infrastructure has been constructed on earthworks pads for the mineral processing plant, the mine operation support units, the open pits of the mines and the areas of waste rock and tailings disposal.

 

If developed, the Phase 2 & 3 project will utilise the infrastructure developed for the Xuxa project.

 

1.15.1Buildings, Roads, Fuel Storage, Power Supply and Water Supply

 

Access to the processing plant will be by municipal roads linking BR367 within the communities of Poço D’antas and Taquaril Seco. The current road will be suitable for truck traffic; however, construction of a new section of the road will be necessary to bypass the plant.

 

The plant and mine services areas will have administrative buildings such as offices, changeroom, cafeteria, concierge, clinic, fire emergency services and operation support facilities such as workshops and warehouses.

 

Fuel will be stored and dispensed from a fuel facility located at the mine services area.

 

Power will be supplied from the existing power grid line. Two main sub-stations (CEMIG and plant) will be installed to supply power to the plant, the mine services area and associated infrastructure.

 

Raw water will be supplied from the Jequitinhonha River, treated as necessary and reticulated within the plant for process, potable and firewater needs.

 

1.15.2Waste Rock and Tailings Disposal and Stockpiles

 

At Xuxa, waste rock will be stored in three waste piles in the vicinity of the Xuxa pits. Geotechnical studies determined an optimal bench height of 20 m, with a face angle of 38°. The access ramps will be 12 m wide, with a maximum gradient of 10%.

 

Table 1-12 shows the capacities of the Xuxa waste piles.

 

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Table 1-12 – Xuxa Waste Pile Storage

 

Designed Pile

Volume

(Mm³)

Area

(ha)

Pile 1 14.9 34.0
Pile 2 43.3 74.3
Pile 3 35.9 55.8
TOTAL 94.1 164.1

 

The Barreiro waste will be stored in a single waste pile close to the Barreiro pit. The waste pile parameters are the same as the Xuxa parameters – a 20 m bench height, 38° face angle, 12 m access ramp and a maximum gradient of 10%.

 

Table 1-13 show the capacity of the Barreiro waste pile.

 

Table 1-13: Barreiro Waste Pile Storage

 

Waste Pile Value
Volume (Mm3) 110.9
Area (ha) 122.7
Maximum height (m) 220

 

The NDC waste will be stored in a single waste stockpile adjacent to the NDC pit. The waste pile parameters are the same as those for Xuxa and Barreiro, namely a 20 m bench height, 38° face angle, 12 m access ramp and a maximum gradient of 10%.

 

Table 1-14 show the capacity of the NDC waste pile.

 

Table 1-14: NDC Waste Pile Capacity and Surface Area

 

Waste Pile Value
Volume (Mm3) 162.5
Area (ha) 158.8
Maximum height (m) 225

 

The tailings stockpile will be fed by a radial stacker from the process plant. The tailings will then be loaded into mine trucks by front end loaders and transported to a tailings pile for storage.

 

1.15.3Control Systems and Communication

 

A process control system (PCS) including a main plant supervisory control and data acquisition (SCADA) system will be installed for monitoring and control purposes.

 

The telecommunications network will consist of the telecommunications network, access control system and radio frequency identification (RFID).

 

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1.16Market Studies and Contracts

 

The key information contained in the market study regarding lithium demand, supply and price forecasts are summarized from Benchmark Mineral Intelligence (2022).

 

1.16.1Demand and Consumption

 

Lithium’s demand growth profile increased dramatically in 2022, driven by structural changes in the automotive industry with manufactures increasingly transitioning towards electric vehicles (“EVs”). Benchmark Mineral Intelligence estimates that 2022 will end in a deficit position with total base-case battery demand expected to end the year at 591 GWh, translating to 475 kt of lithium carbonate equivalent (“LCE”) demand, up from 348kt LCE in 2022. Total lithium demand in 2022 expected to be 613 kt of LCE vs 482 kt in 2021.

 

Benchmark Mineral Intelligence estimates that the supply-demand balance will tighten further going forward, with 2023 forecasted to have a base case demand from battery end-use of 630 kt LCE, a 33% increase from 2022. This deficit position is expected to continue to increase, reaching a net deficit position of 159 kt LCE by 2030 and 2,580 kt LCE by 2040.

 

Benchmark Mineral Intelligence estimates global EV penetration will reach 12.4% in 2022, up from 8.0% in 2021, as global EV sales continue to accelerate, particularly from Europe and China. This figure is expected to climb to 21% by 2025 and reach 74% by 2040.

 

1.16.2Supply

 

Benchmark Mineral Intelligence expects lithium supply to increase over the 634 kt LCE of total supply estimated in 2022, given the robust commodity price outlook for lithium.

 

In the longer term, Benchmark Mineral Intelligence forecasts that the total lithium supply will reach 2.1 Mt LCE by 2030 and 3.0Mt LCE by 2040. Benchmark Mineral Intelligence’s supply forecast includes expansions from existing mines as well as new entrants developing pre-production projects.

 

1.16.3Price Forecast

 

Tight market supply combined with rapidly improving demand for lithium chemicals is expected to put continued strong upward pressure on prices. Benchmark Mineral Intelligence’s base case forecast expects prices to continue to rise through 2023 as demand outstrips supply with real lithium hydroxide and spodumene 6% prices hitting US$55,900/t and US$5,100/t in 2023, respectively. Benchmark then expects prices to stabilize at higher levels in 2024 and begin to decline to more stable levels in a balanced supply-demand market in 2025.

 

1.16.4Contracts

 

1.16.4.1Off-Take Agreements

 

On October 6, 2021, Sigma announced the signing of a binding term sheet for an offtake agreement on a “take or pay” basis (LGES Offtake) for the sale of up to 100,000 tonnes per year of battery grade lithium concentrate to LG Energy Solution, Ltd (LGES), one of the world’s largest manufacturers of advanced lithium-ion batteries for EVs.

 

The six-year LGES Offtake starts with 60,000 tonnes per year in 2023 and is expected to increase to 100,000 tonnes per year from 2024 to 2027 (Guaranteed Take-or-Pay Quantity), subject to Sigma and LGES executing mutually acceptable definitive documentation to implement the LGES Offtake. Sigma and LGES are also to negotiate each year, starting in 2022, an additional optional supply of battery grade lithium concentrate (Optional Offtake Quantity), not otherwise committed by Sigma in other offtake arrangements.

 

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Pursuant to the LGES Offtake, Sigma will receive a price for the delivered battery grade lithium concentrate linked to the market prices for high purity lithium hydroxide.

 

1.16.4.2Operational Contracts

 

Sigma has no contracts in place in support of operations. but is in negotiations with respect to a number of contracts pertaining to mining contracting, road transport, port handling and power. Any future contracts are likely to be negotiated and renewed on an annual or biannual basis. Contract terms are expected to be typical of similar contracts in Minas Gerais State.

 

Contracts currently under negotiation include the mining contract, road transport contract, port handling contract and the power contract.

 

1.16.4.3Construction contracts

 

Sigma has signed an agreement for the EPCM of the Production Plant and associated infrastructure with engineering firm Promon Engenharia Ltda (“Promon”). Detailed engineering is completed in collaboration of Promon and Primero Group Ltd (“Primero”). The detail engineering is progressing according to priority and both companies started issuing construction drawings according to the schedule baseline. Procurement services according to the Procurement Plan defined in the FEED. Construction Management includes general scheduling, managing all items, generating weekly dash boards, preparing presentations with critical points, preventive and corrective actions in order to reach the project deadlines.

 

Sigma has signed an agreement for the civil construction of the Production Plant with engineering firm Tucumann Engenharia e Empreendimentos Ltda (“Tucumann”). The scope of work includes all civil construction works and services for the implementation of the Project, including the supply of materials, commissioning, provision of documentation, topographic survey services, excavations, shallow foundations, concrete structures, buildings, paving, streets, urbanization and landscaping and rainwater drainage and spare parts.

 

Sigma has signed an agreement for the construction of a substation and the displacement of an existing transmission line with Tecnova Engenharia Ltda (“Tecnova”). The scope of work includes all civil construction, electromechanical and electrical assembly works and services for the implementation of the including, the civil project, the electrical project, the electromechanical project, the supply and installation of materials, structures and equipment, as well as commissioning, supply of documentation as built of the civil, electromechanical and electrical works, considering all the technical information informed by CEMIG.

 

Sigma has signed an agreement for the construction of a laboratory with SGS Geosol Laboratórios Ltda (“SGS Geosol”). The scope of work includes all work for the management of the assembly of the Sigma's internal laboratory and implementation, including the electrical project, the electromechanical project (including, but not limited to, the drawings, layouts, technical specifications, bills of materials, calculation memorials and documents), hydraulic design, supply and installation of materials, structures and equipment, as well as commissioning, start-up, supply of "as built" documentation of the projects, electromechanical, hydraulic and electrical, and all other services necessary for the execution of the scope of work

 

1.17Environmental Studies, Permitting and Social or Community Impact

 

Conselho Estadual de Politica Ambiental (COPAM) granted an Operation License in support of certain SMSA mining concessions on the Grota do Cirilo property on August 25, 1994. The licence was renewed on August 14, 2008 but has subsequently been allowed to lapse as it was not suitable for the new level of mining contemplated by Sigma. Sigma applied and was issued the first phase of the Preliminary License (Licença Previa or LP) and an Installation License (Licença de Instalação or LI) to commence construction at the Xuxa deposit. Mining licenses are for life of mine and environmental licences are timely renewed when due.

 

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Sigma holds approved economic mining plans (Plano de Aproveitamento Econômico or PAE) over the Xuxa, Barreiro, Lavra do Meio, Murial, Maxixe and Nezinho do Chicâo deposits within the Grota do Cirilo property. The PAE for Xuxa was updated and approved in August 2018, while the PAE for Barreiro was updated and approved in July 2022.

 

Reclamation plans (referred to as degraded area plans or PRADs) have been developed and implemented for certain past-producing areas within the Grota do Cirilo property. The successful recovery of these areas is managed by SMSA personnel and external consultants in conjunction with the governing regulatory agencies.

 

Sigma has held regular meetings and consultation sessions with local stakeholders regularly over the last five years. The further development of SMSA mining activities in the Jequitinhonha Valley is viewed by both communities as an important regional economic driver.

 

1.17.1Applicable Legal Requirements for Project Environmental Permitting

 

CONAMA Resolution N° 237 (1997) defines environmental licensing as an administrative procedure by which the competent environmental agency permits the locating, installation, expansion and operation of enterprises and activities that use environmental resources in a manner considered to be effectively or potentially polluting.

 

The licensing process in Minas Gerais has been developed in accordance with COPAM Regulatory Deliberation N° 217, dated December 6, 2017, and establishes classification criteria based on scale and polluting potential, as well as the locational criteria used to define the modalities of environmental licensing of ventures and activities that use environmental resources in the state of Minas Gerais.

 

In compliance with CONAMA Resolution 09/90, the environmental licensing of mining projects is always subject to an Environmental Impact Assessment (EIS), followed by an Environmental Impact Report (EIR), which supports the technical and environmental feasibility stage of the project and the granting of a LP and/or a concurrent LP + LI.

 

1.17.2Current Project Environmental Permitting Status

 

The water license for the uptake of 150 m³/hr of water from the Jequitinhonha River was approved by the Agencia Nacional das Águas (ANA) in February 2019.

 

The CEL 2 (LP + LI) (installation licence) for the initial project phase, consisting of the north pit (Pit #1), waste piles 1 and 2 and the plant area was submitted on December 20, 2018 and was followed by the complete presentation of the EIS, the EIR and the Environmental Control Plan (ECP) as well the other documents listed in Basic Guidance Form (BGF). The EIS (Estudo e Relatorio de Impacto Ambiental – EIA-RIMA dated 30 October 2018) and Plano de Controle Ambiental – PCA dated December 2018 were prepared and issued for submittal to the authorities by NEO Soluções Ambientais and ATTO GEO Geologia e Engenharia. Approval was obtained on June 3, 2019.

 

A second EIS covering Pit #2 and waste piles #3 and #4 was formally approved in July 2022 in line with the prescribed permitting timing requirements for the process plant coming online with Pit #1.

 

1.17.3Authorization

 

SMSA is the owner of the mining rights registered under DNPM Nº 824.692/1971, and the holder of Mining Concession Ordinance Nº 1.366, published on October 19, 1984. In 2018 a new Economic Development Plan (EDP) was registered with the National Mining Agency (ANM), which was approved on November 16, 2018.

 

The approval of the EDP and environmental study involves the technical and legal analysis and formal approval of the proposed project. With the granted LP + LI, the company must now install the project within 5 years, comply with the environmental conditions established in the LP + LI certificate and finally, apply for the Operation License after installation in order to begin operational activities.

 

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The formalization of the environmental licensing process also included requesting and granting of the EIA.

 

1.17.4Land Access

 

Sigma has a lease agreement with Miazga Participações S.A., owner of the Poço Danta-Paiuí, Poço Danta and Poço Dantas Farms, to carry out mining activities on its properties. These farms include Legal Reserves (LR) which are preserved and registered in the National Rural Environmental Registration System (NRERS), in accordance with Law Nº 12.651, dated May 25, 2012.

 

Sigma is also leasing the following individual farms: Lucinéia Fátima de Souza, Demostenes Vieira Filho, Jose Antonio Teixeira dos Santos, Ildete Faria, Vanusia Santos, Nixon Borges, Sandro Araújo, Claudenice Silva, Ustane Ribeiro, Nizoeiro Souza, Lourivaldo Araujo and Joaquim Ferreira Santos.

 

1.17.5Social License Considerations

 

Sigma understands and accepts the importance of proactive community relations as an overriding principle in its day-to-day operations as well as future development planning. The company therefore structures its community relations activities to consider the concerns of the local people and endeavors to communicate and demonstrate its commitment in terms that can be best appreciated and understood to maintain the social license to operate.

 

The Jequitinhonha valley is the poorest region in Minas Gerais which is plighted by poverty and is in the lowest quartile the Human Development Index (HDI). Sigma is the largest investment and operation in the area by a factor of ten and the project will be transformational to the local communities. The largest direct economic benefit is that Sigma is subject to a 2% royalty on revenue which is divided between the Federal Government, State Government and Local Government. Secondly a portion of the taxes on local procurement of goods and services is shared with the Local Government. These incomes from the royalty and tax are a most important source of funding for local Government and Sigma is the largest direct contributor in the region. Sigma will be by far the largest employer in the region with an estimated 500 direct jobs being created with 3 to 4 times this number being indirect.

 

Farming in the area is small-scale subsistence type as the area is semi-arid. There is minimal impact on the neighbouring farms of Grota do Cirilo properties. Sigma and contractor workforce will live in the cities of Araçuaí and Itinga and strict environmental management plans are in place to minimize the environmental footprint of the project. An example is 90% of the process water is re-circulated and there is zero run-off water from the site except during the wet season, when excess water from the pond will be discharged in an overflow channel. The process uses dry stacking technology, and no slimes dam will be built. Regular environmental monitoring will be conducted, and results will be shared with the local communities.

 

Sigma has targeted and continues with consultations/engagements with numerous stakeholders in support of project development of the Project and has hosted visits from representatives of government departments and local academic institutions.

 

1.17.6Rehabilitation, Closure Planning and Post-Closure Monitoring

 

The closure plan for the Grota do Cirilo property encompasses the following: dismantling of building and infrastructure, removal of heavy mobile and surface equipment, restoration by reconstituting vegetal cover of the soil and the establishment of the native vegetation, grading and capping with vegetation suppression layer and revegetation of the waste rock and overburden stockpiles, removal of suppressed vegetation along with slope cover and surface drainage for water management, fencing of site, environmental liability assessment studies where there may have been spillages and soil and water contamination and safe disposal, revegetation of the open pit berm areas and fencing around the open pits.

 

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In the post-closure phase, a socioenvironmental and geotechnical monitoring program will be carried out, to support ecosystem restoration or preparation for the proposed future use.

 

The monitoring program will collect soil and diversity of species on an annual basis, continuing for a five-year period after mine closure.

 

1.17.7Barreiro Environmental Work to Date

 

The Preliminary License - LP and an Installation License - LI for- Barreiro Pegmatite was approved in July 2022.

 

The license allows for the mining of 1,800,000 t/year for open pit mining and 251.89 ha for waste piles.

 

1.17.8NDC Environmental Work to Date

 

The Environmental Impact Study - EIA and its respective Environmental Impact Report – RIMA will be submitted to the regulatory agency, Superintendence of Priority Projects - SUPPRI, as a supporting document for obtaining a Preliminary License - LP and Installation License - LI for the Grota do Cirilo Project - Pegmatite from Nezinho do Chicão.

 

Considering the parameters defined by the laws and regulations in force, CONAMA Resolution 09/90, the environmental licensing of mining projects is conditioned to the submission of the EIA/RIMA, these studies being the main technical resources to assess the viability of the projects.

 

The environmental licensing process began in December 2022 and will be formalized with the presentation of the technical studies requested through the Environmental Licensing System - SLA, for the production of 1,700,000 t/year for open pit mining and 182, 2 ha for waste piles.

 

1.18Capital and Operating Costs

 

1.18.1Capital Cost Estimate

 

The capital cost estimate (CAPEX) was developed to provide substantiated costs for the FEED study of Phase 1 and the PFS-level study of Phase 2 & 3 processing plant and to provide Sigma with an overall risk and opportunity profile to enable a Phase 1 production decision and to advance off-take agreements and project financing.

 

The total CAPEX for Phase 1 including the Estimated Vat Tax Incentive is US$130.6 M.

 

The total Capex for Phase 2 & 3 is US$154.9 M (this is including the Owner’s cost, working capital, contingency and excluding the Sustaining Capital).

 

The CAPEX estimate has an accuracy of ±25% and is summarized in Table 1-15 (Phase 1) and Table 1-16 (Phase 2 & 3).

 

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able 1-15 – Capital Cost Estimate Summary Phase 1

 

AREA TOTALS
  (USD)
  DIRECTS + INDIRECTS CONTINGENCY TOTAL
  (USD) (USD) (USD)
001 MINE  7,856,938    605,014    8,461,952  
002 PLANT  64,841,255    4,992,777    69,834,032  
002.003 AUTOMATION/DIGITALIZATION  3,852,981    296,680    4,149,661  
003 ENVIRONMENTAL  14,418,492    1,121,428    15,539,921  
004 EPCM & ENGINEERING SERVICES  17,867,543    1,375,801    19,243,344  
005 SUBSTATION & UTILITY POWER SUPPLY  6,888,863    530,442    7,419,305  
Total Construction Capital Cost  111,873,091    8,625,462    120,498,553  
006 OWNERS PROJECT COSTS  8,901,677    890,168    9,791,844  
007.001 Working Capital and Spares  6,137,293    –    6,137,293  
Total Construction Capital Cost (ex VAT Tax Incentive)  126,912,061    9,515,630    136,427,691  
009 Estimated VAT Tax Incentive (5,859,000)  –   (5,859,000)
Total Construction Capital Cost  121,053,061    9,515,630    130,568,691  
       
008 Sustaining and Deferred Capital 3,200,000 246,400  3,446,400  

 

Table 1-16: Capital Cost Estimate Summary Phase 2 & 3

 

AREA TOTALS
(USD)    
MEGA PLANT DIRECTS + INDIRECTS CONTINGENCY TOTAL
(USD) (USD) (Excluding recoverables)
    (USD)
       
000 MEGA (Excluding Sustaining Capital) 144,429,471 10,473,002 154,902,473
000 MEGA (Including Sustaining Capital) 157,499,471 11,479,392 168,978,863
001 MINE 2,096,208 161,408 2,257,616
002 PLANT 89,536,397 6,718,807 96,255,204
003 ENVIRONMENTAL 15,252,504 1,174,443 16,426,946
004 EPCM & ENGINEERING SERVICES 21,672,011 1,668,745 23,340,755
005 SUBSTATION & UTILITY POWER SUPPLY 663,829 51,115 714,943
006 OWNERS PROJECT COSTS 9,071,230 698,485 9,769,715
007 WORKING CAPITAL & SPARES 6,137,293 0 6,137,293
008  SUSTAINING & DEFERRED CAPITAL 13,070,000 1,006,390 14,076,390

 

Note: The Phase 2 & 3 substation costs are included in the Xuxa CAPEX estimate

 

1.18.2Operating Cost Estimate

 

The processing plant operating cost estimate includes the operation of a three-stage crushing and screening circuit and DMS circuits (two stages for coarse, fine and ultra fines material classes).

 

The processing OPEX includes operating and maintenance labour, power, fuel and indirect charges associated with the processing plant. Based on these cost assumptions, inclusions and exclusions, it is estimated that the variable OPEX for the Phase 1 concentrator will be $5.3/t of ore feed and US$7.5M of fixed OPEX. The estimated variable OPEX for the Phase 2 & 3 concentrator is $4.8/t of ore feed and US$6.7M of fixed OPEX.

 

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Operating cost estimates are summarized in Table 1-17 (Phase 1) and Table 1-18 (Phase 2 & 3)

 

Table 1-17: Phase 1 Operating Cost Estimate Summary

 

DESCRIPTION OPEX (US$)
Mining (US$/t material mined) $2.1
Process (US$/t ore feed) $10.4
G&A (US$/t ore feed) $5.3
Shipping (US$/t SC) $120

 

Table 1-18: Phase 2 & 3 Operating Cost Estimate Summary

 

DESCRIPTION OPEX (US$)
Barreiro Mining (US$/t material mined) $2.68
NDC Mining (US$/t material mined) $1.98
Phase 2 & 3 Process (US$/t ore feed) $7.1
Phase 2 & 3 G&A (US$/t ore feed) $2.7
Shipping (US$/t SC) $120

 

1.19Economic Analysis

 

1.19.1Economic Assumptions

 

Three levels of economic analyses were undertaken for the Project, contemplating the mining of the Mineral Reserves of:

 

·the Xuxa deposit (Phase 1)

·the Barreiro and NDC deposits (Phase 2 & 3) and

·both Phase 1 and Phase 2 & 3 (Phase 1, 2 & 3)

 

The Phase 1, 2 & 3 analysis has been selected as the best growth and integrated plan for the Grota Do Cirilo Project.

 

The economic analyses contemplate the production of spodumene concentrate (SC) at grades of 5.5% Li2O, in line with the current lithium market conditions.

 

The base case scenario after-tax net present value (NPV) results are detailed in Table 1-19 below. The discount rate assumed for the after-tax NPVs is 8%.

 

A sensitivity analysis reveals that the Project’s viability will not be significantly vulnerable to variations in capital expenditures, within the margins of error associated with the DFS and study estimates for Phase 1 and Phase 2 & 3, respectively. In contrast, the Project’s economic returns remain most sensitive to changes in spodumene prices, feedstock grades and recovery rates.

 

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Table 1-19 – Base Case After-Tax NPVs

 

Modelled Case Unit @ 5.5% SC
Phase 1 US$ M $5,699
Phase 2 & 3 US$ M $9,587
Phase 1, 2 & 3 US$ M $15,289

 

Phase 1, Phase 2 & 3 and Phase 1, 2 & 3 were evaluated on a pre- and after-tax basis. It must be noted that there are many potential complex factors that affect the taxation of a mining project. The taxes, depletion, and depreciation calculations in the economic analyses are simplified and only intended to give a general indication of the potential tax implications at the project level.

 

Sudene is a government agency tasked with stimulating economic development in specific geographies of Brazil. The project is to be installed in a Sudene-covered geographic area, where a tax incentive granted to the project indicates a 75% reduction of income tax for 10 years, after achieving at least 20% of its production capacity. The considered Brazilian income tax rate is assumed to be 15.25%, which represents the Sudene tax benefit applied to the Brazilian maximum corporate tax of 34% on taxable income (25% income tax plus 9% social contribution). For Phase 2 & 3, the Sudene tax incentive is expected to be renewed after the 10th anniversary of achieving at least 20% of their production capacities.

 

The Project is expected to be exempt from all importation taxes for products which there is no similar item produced in Brazil (Ex-Tarifário). Assembled equipment where some but not all individual components are produced in Brazil can be considered exempt from import taxes under these terms.

 

The Project royalties will include:

 

·A 2.0% CFEM royalty on gross spodumene revenue, paid to the Brazilian Government. The CFEM royalty amount is split between the Federal Government of Brazil (12%), State Government of Minas Gerais (23%), and Municipal Government of Araçuaí (65%).

·A 1.0% NSR royalty with permissible deductions from gross spodumene revenue including the CFEM royalty, any commercial discounts, transportation costs and taxes paid.

·A 1.0% NSR royalty with permissible deductions including all of the costs associated with production; however, this royalty has a buyback provision for US$3.8 million which is assumed to be exercised upon achieving commercial production in the Phase 1, Phase 2 & 3 and Phase 1, 2 & 3 analyses.

 

1.19.2Phase 1 DFS Economic Analysis

 

The Phase 1 economic analysis is based on an eight-year operation sourcing feedstock ore from the Xuxa deposit’s Mineral Reserve of 11.8 Mt grading at 1.55% Li2O. Phase 1 is expected to generate run-rate production of 270 ktpa of lithium concentrate, delivering US$990 million of annual free cash flow, at a 5.5% SC grade.

 

The base case scenario results are detailed in Table 1-20 below.

 

Table 1-20: Phase 1 Base Case Scenario Results

 

Item Unit @ 5.5% SC
After-Tax NPV @ 8% US$ M $5,699
After-Tax IRR % 1,282%
After-Tax Payback Period Years 0.1

 

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The key technical assumptions used in the base case are highlighted below in Table 1-21.

 

Table 1-21: Key Phase 1 Technical Assumptions

 

Item Unit @ 5.5% SC
Total Ore Processed (ROM) Mt 11.8
Annual ROM Ore Processed Mt 1.5
Run-Rate SC Production Ktpa 270
Run-Rate LCE Production (Note 1) Ktpa 37
Strip Ratio Ratio 16.4: 1
Average Li2O Grade % 1.55%
Spodumene Recovery Rate % 65.0%
Spodumene Concentrate Grade % Li2O 5.5%
Operating Life Years 8
Total Cash Cost Ex. Royalties (@ Mine Gate) US$/t SC $288
Total Cash Cost Incl. Royalties (@ Mine Gate) US$/t SC $419
Transportation Costs (CIF China) US$/t SC $120
Total Cash Cost (CIF China) US$/t SC $539
AISC (CIF China) US$/t SC $541
Mining Costs US$/t Material Mined $2.06
Processing Costs US$/t ROM $10.38
G&A Costs US$/t ROM $5.29

 

Note 1: tonnage based on direct conversion to LCE excluding conversion rate

 

The total gross revenue derived from the sale of spodumene concentrate is estimated at US$10.6 billion, an average revenue of US$4,909/t 5.5% SC with total operating costs (including royalty payments and commercial discounts) of US$1.3 billion at an average cost of US$581/t 5.5% SC. The resulting after-tax earnings margin (gross revenue less realization, operating costs and taxes) was estimated at US$7.9 billion.

 

A sensitivity analysis for Phase 1 was carried out with the base case as the midpoint. An interval of ±20% versus base case values was considered with increments of 10%.

 

Phase 1 after-tax NPV is not significantly vulnerable to changes in BRL to US$ exchange rate, CAPEX, OPEX, or discount rate considered. In contrast, Phase 1 after-tax NPV is more sensitive to variation in spodumene price, lithium grade, and spodumene recovery rates.

 

Phase 1 after-tax IRR is not significantly vulnerable to changes in OPEX. In contrast, Phase 1 after-tax IRR is more sensitive to variation in spodumene price, lithium grade, spodumene recovery rates, BRL to US$ exchange rate and CAPEX. Note that the Phase 1 after-tax IRR is independent of the discount rate considered.

 

1.19.3Phase 2 & 3 PFS Economic Analysis

 

The Phase 2 & 3 PFS economic analysis is based on a twelve-year operation sourcing feedstock ore from the Barreiro deposit’s Mineral Reserve of 21.8 Mt grading at 1.37% Li2O and the NDC deposit’s Mineral Reserve of 21.2 Mt grading at 1.45% Li2O. Phase 2 & 3 is expected to generate run-rate production of 496 ktpa of lithium concentrate, delivering US$1,179 M of annual free cash flow, at a 5.5% SC grade.

 

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The base case scenario results are detailed in Table 1-22 below.

 

Table 1-22: Phase 2 & 3 Base Case Scenario Results

 

Item Unit @ 5.5% SC
After-Tax NPV @ 8% US$ M $9,587
After-Tax IRR % 1,207%
After-Tax Payback Period Years 0.1

 

The key technical assumptions used in the base case are highlighted below in Table 1-23.

 

Table 1-23: Key Phase 2 & 3 Technical Assumptions

 

Item Unit @ 5.5% SC
Total Ore Processed (ROM) Mt 42.9
Annual ROM Ore Processed Mt 3.3
Run-Rate SC Production Ktpa 496
Run-Rate LCE Production (Note 1) Ktpa 67
Phase 2 Strip Ratio Ratio 12.5: 1
Phase 3 Strip Ratio Ratio 16.0: 1
Phase 2 Average Li2O Grade % 1.36%
Phase 3 Average Li2O Grade % 1.45%
Phase 2 Spodumene Recovery Rate % 57.9%
Phase 3 Spodumene Recovery Rate % 50.6%
Spodumene Concentrate Grade % Li2O 5.5%
Operating Life Years 12
Total Cash Cost ex. Royalties (@ Mine Gate) US$/t SC $292
Total Cash Cost incl. Royalties (@ Mine Gate) US$/t SC $394
Transportation Costs (CIF China) US$/t SC $120
Total Cash Cost (CIF China) US$/t SC $514
AISC (CIF China) US$/t SC $516
Mining Costs US$/t Material Mined $2.25
Processing Costs US$/t ROM $7.06
G&A Costs US$/t ROM $2.68

 

Note 1: tonnage based on direct conversion to LCE excluding conversion rate

 

The total gross revenue derived from the sale of spodumene concentrate is estimated at US$21.5 billion, an average revenue of US$3,610/t 5.5% SC with total operating costs (including royalty payments and commercial discounts) of US$3.4 billion at an average cost of US$569/t 5.5% SC. The resulting after-tax earnings margin (gross revenue less realization, operating costs and taxes) was estimated at US$15.3 billion.

 

A sensitivity analysis for Phase 2 & 3 was carried out with the base case as described above as the midpoint. An interval of ±20% versus base case values was considered with increments of 10%.

 

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Phase 2 & 3 after-tax NPV is not significantly vulnerable to changes in BRL to US$ exchange rate, CAPEX, OPEX, or discount rate considered. In contrast, Phase 2 & 3 after-tax NPV is more sensitive to variation in spodumene price, lithium grade, and spodumene recovery rates.

 

Phase 2 & 3 after-tax IRR is not significantly vulnerable to changes in OPEX. In contrast, Phase 2 & 3 after-tax IRR is more sensitive to variation in spodumene price, lithium grade, spodumene recovery rates, BRL to US$ exchange rate and Capex. Note that the Phase 2 & 3 after-tax IRR is independent of the discount rate considered.

 

1.19.4Phase 1, 2 & 3 Economic Analysis

 

The Phase 1, 2 & 3 economic analysis is based on a thirteen-year operation sourcing feedstock ore from the Xuxa deposit’s Mineral Reserve of 11.8 Mt grading at 1.55% Li2O, Barreiro deposit’s Mineral Reserve of 21.8 Mt grading at 1.37% Li2O and the NDC deposit’s Mineral Reserve of 21.2 Mt grading at 1.45% Li2O. Phase 1, 2 & 3 is expected to generate run-rate production of up to 766 ktpa of lithium concentrate, delivering US$1,788 million of annual free cash flow, at a 5.5% SC grade.

 

The base case scenario results are detailed in Table 1-24 below.

 

Table 1-24: Phase 1, 2 & 3 Base Case Scenario Results

 

Item Unit @ 5.5% SC
After-Tax NPV @ 8% US$ M $15,289
After-Tax IRR % 1,273%
After-Tax Payback Period Years 0.1

 

The key technical assumptions used in the base case are highlighted below in Table 1-25.

 

Table 1-25: Key Phase 1, 2 & 3 Technical Assumptions

 

Item Unit @ 5.5% SC
Total Ore Processed (ROM) Mt 54.7
Annual ROM Ore Processed Mt 4.2
Run-Rate SC Production ktpa 766
Run-Rate LCE Production (Note 1) ktpa 104
Phase 1 Strip Ratio ratio 16.4: 1
Phase 2 Strip Ratio ratio 12.5: 1
Phase 3 Strip Ratio ratio 16.0: 1
Phase 1 Average Li2O Grade % 1.55%
Phase 2 Average Li2O Grade % 1.36%
Phase 3 Average Li2O Grade % 1.45%
Phase 1 Spodumene Recovery Rate % 65.0%
Phase 2 Spodumene Recovery Rate % 57.9%
Phase 3 Spodumene Recovery Rate % 50.6%
Spodumene Concentrate Grade % Li2O 5.5%
Operating Life years 13
Total Cash Cost ex. Royalties (@ Mine Gate) US$/t SC $289
Total Cash Cost incl. Royalties (@ Mine Gate) US$/t SC $401
Transportation Costs (CIF China) US$/t SC $120
Total Cash Cost (CIF China) US$/t SC $521
AISC (CIF China) US$/t SC $523
Mining Costs US$/t Material Mined $2.20
Processing Costs US$/t ROM $7.78
G&A Costs US$/t ROM $3.24

 

Note 1: tonnage based on direct conversion to LCE excluding conversion rate

 

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the total gross revenue derived from the sale of spodumene concentrate is estimated at US$32.1 billion, an average revenue of US$3,956/t 5.5% SC with total operating costs (including royalty payments and commercial discounts) of US$4.6 billion at an average cost of US$572/t 5.5% SC. The resulting after-tax earnings margin (gross revenue less realization, operating costs and taxes) was estimated at US$23.3 billion.

 

A sensitivity analysis for Phase 1, 2 & 3 was carried out with the base case as described above as the midpoint. An interval of ±20% versus base case values was considered with increments of 10%.

 

Phase 1, 2 & 3 after-tax NPV is not significantly vulnerable to changes in BRL to US$ exchange rate, CAPEX, OPEX, or discount rate considered. In contrast, Phase 1, 2 & 3 after-tax NPV is more sensitive to variation in spodumene price, lithium grade, and spodumene recovery rates.

 

Phase 1, 2 & 3 after-tax IRR is not significantly vulnerable to changes in OPEX. In contrast, Phase 1, 2 & 3 after-tax IRR is more sensitive to variation in spodumene price, lithium grade, spodumene recovery rates, BRL to US$ exchange rate and Capex. Note that the Phase 1, 2 & 3 after-tax IRR is independent of the discount rate considered.

 

1.20Interpretation and Conclusions

 

Mineral Resources are reported for five pegmatite bodies, Xuxa, Barreiro, Murial, Lavra do Meio and Nezinho do Chicao. Mineral Reserves are reported for the Xuxa, Barreiro and NDC deposits.

 

This report contains the updated Phase 3 Mineral Resource Estimate (MRE) and the maiden Mineral Reserve Estimate for the Nezinho do Chicao (NDC) pegmatite and a PFS-level study for Phase 2 & 3 of the project.

 

1.20.1Risk Assessment

 

Risk assessment sessions were conducted individually and collectively by all parties.

 

Most aspects of the project are well defined. The risks are grouped by licensing, cost (CAPEX and OPEX), schedule, operations, markets, and social/environmental categories. One of the most significant risks identified for the Project is related to lithium markets.

 

The following risks are highlighted for the project:

 

·Lithium market sale price and demand (commercial trends)

·Delay in receiving the Environmental Operation License

·Delay in obtaining the power permit and CEMIG substation energization: impact on plant start-up date

·Delay in obtaining the license for Barreiro Pit

 

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·Fluctuations in the exchange rate and inflation

·Labour strikes at the Port and at site (construction and operation)

·Tax exemptions and import not confirmed

·Increased demands from the local community once in operation

·More fines generated from mining and crushing: potential negative impact on recovery

·The production rate and size of the pit may impose challenges for operations

·Waste generation: the continuous geotechnical monitoring system to be implemented during mining operation can indicate local changes to geotechnical parameters, and potential increase of waste

 

1.20.2Opportunities

 

The following opportunities are identified for the Grota do Cirilo Project:

 

·Recovery of Li2O from hypofines with a flotation circuit

·Sales of hypofines as DSO

·Recovery of Li2O from petalite

·Sale of plant rejects to the ceramics industry

·Potential upgrading of some or all of the Inferred Mineral Resources to higher-confidence categories and eventually conversion to Mineral Reserves

·Potential for future underground mining at both Phase 1 and Phase 2 projects.

·Exchange rate may work in the Project’s favour.

 

1.21Recommendations

 

The following summarizes the recommendations from the Updated Technical Report.

 

1.21.1Engineering

 

Based on the results of the NDC PFS, the QPs recommend:

 

·The Company proceed to completing a definitive feasibility study (DFS) in respect of the Nezinho do Chicao deposit. Estimated cost US$ 1,000,000

·Complete studies relating to mine and waste heap geotechnics and hydrogeology considering geotechnical borehole completion, borehole geotechnical logging and a bore hole televiewer program.

 

1.21.2Geology and Resources

 

The QPs recommend that additional exploration drilling be conducted across the Xuxa, Barreiro, NDC and Murial deposit to update existing resources and potentially increase resources. The overall cost for the drill program is estimated to be US$ 12.4 M dollars

 

1.21.3Recovery and Infrastructure

 

The following are the recommendations form the QPs for recovery and infrastructure:

 

·Undertake a petalite recovery study on Barreiro ore

·Review the infrastructure requirements for Phase 2 & 3

 

1.21.4Economic Analysis

 

The QPs recommend undertaking a Front-End Engineering Design (FEED) on Phase 2 & 3.

 

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2INTRODUCTION

 

Sigma Lithium Corporation (Sigma) requested Primero Group Americas Inc. (Primero), a division of Primero Group Ltd, together with SGS Geological Services (SGS), GE21 Consultoria Mineral (GE21) and Promon Engenharia Ltda (Promon) to prepare a Technical Report (the Report) for the Sigma’s Grota do Cirilo Project located in Minas Gerais State, Brazil. (Figure 2 1). This includes an updated Mineral Resource estimate and a maiden Mineral Reserve estimate for the Phase 3 Nezinho do Chicao (NDC) deposit.

 

 

Figure 2-1: Project Location

 

2.1Terms of Reference

 

Mineral Resources are reported for five pegmatite bodies, Nezinho do Chicao, Xuxa, Barreiro, Murial and Lavra do Meio. Mineral Reserves are reported for the Xuxa and Barreiro deposits. A feasibility study has been conducted on the Xuxa deposit and a pre-feasibility level study has been conducted on the Barreiro deposit (project phase 2).

 

Mineral Resources and Mineral Reserves are reported using the 2014 Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Definition Standards (2014 CIM Definition Standards).

 

This Report is based, in part, on internal reports and information as listed in Section 27 of this Report. Where sections from reports authored by other consultants have been directly quoted in this Report, they are indicated as such in the Report sections.

 

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2.2Effective Dates

 

The effective date of the Xuxa Mineral Resource estimate is January 10, 2019.

 

The effective date of the Xuxa Mineral Reserve estimate is June 21, 2021

 

The effective date of the Barreiro Mineral Resource estimate is February 24, 2022.

 

The effective date of the Barreiro Mineral Reserve estimate is February 24, 2022.

 

The effective date of the financial analysis supporting the Barreiro Mineral Reserve is February 24, 2022.

 

The effective date of the NDC Mineral Resource estimate is October 31, 2022.

 

The effective date of the NDC Mineral Reserve estimate is October 31, 2022.

 

The overall effective date of the Updated Technical Report is the date of the financial analysis supporting the NDC Mineral Reserves and is October 31, 2022.

 

2.3Qualified Persons

 

This Technical Report was prepared for Sigma by or under the supervision of the following Qualified Persons (QPs):

 

·Mr. Homero Delboni Jr, MAusIMM (CP), Senior Consultant, HDA Serviços S/S Ltda

·Mr. Marc-Antoine Laporte, P.Geo., Senior Geologist, SGS

·Mr. Jarrett Quinn, P.Eng., Lead Process Engineer, Primero Group Americas

·Mr. Porfirio Cabaleiro Rodriguez, FAIG, Senior Director GE21

·Mr. Noel O’Brien, FAusIMM, Metallurgical Consultant, Trinol Pty Ltd

 

2.4Site Visits

 

The following Qualified Persons visited the Project site.

 

Mr. Marc-Antoine Laporte visited the Project site on September 11–15, 2017, from July 11–17, 2018, from September 18-23, 2018, from October 18-21, 2021 and from May 30 to June 1 2022. During the 2017 site visit, Mr. Laporte conducted a general review of the logging and QA/QC procedures in place for the 2017 drill program. Drill hole collars were visited, and selected collar positions checked with a hand-held global positioning system (GPS) instrument. An inspection of the drilling equipment and deviation survey methodology and tools was completed. Mr. Laporte took 26 witness (control) samples from the remaining 2014 Xuxa campaign drill core to submit for independent confirmation of the presence of lithium-bearing mineralization. During the July 2018 site visit a general review of the logging and QA/QC procedure was conducted with Sigma geologists to confirm compliance with industry best practices. Drill hole collars at Xuxa, Barreiro and Lavra Do Meio were inspected, and selected collar positions checked with a hand-held GPS instrument. An extensive review of the mineralized core from the four main pegmatite was conducted during the first two days of the visit including discussion of the sampling method with technical staff. Inspection of the drilling equipment and deviation survey methodology and tools between the two drilling companies was also completed to check consistency between the drill teams. One day was spent on the Sao Jose property to inspect the different historical mine workings and make recommendations for future drilling. Mr. Laporte visited the site again in September 2018, where he discussed the geological model and information needed to complete the resource estimates on the Xuxa, Barreiro, Murial and Lavra do Meio pegmatites. On his site visit in 2021, Mr. Laporte reviewed logging, QAQC and the drilling program underway at the Barreiro deposit. He also discussed the geological model and the information needed to update the MRE for Barreiro.

 

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Mr. Porfirio Cabaleiro Rodriguez visited the site from April 17-18, 2019, and from 25-29 July 2022. During these visit, he familiarized himself with general aspects of the proposed mine areas, and locations for future waste pile areas and the planned plant site area. Mr. Rodriguez observed the possible influence of the Piauí River on the planned pits, and the general aspects of rock behavior based on the observation of excavations.

 

2.5Information Source

 

Sigma provided the financial model for the economic study. Primero has reviewed the model and input files for alignment with the Project input data.

 

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3RELIANCE ON OTHER EXPERTS

 

3.1Marketing

 

The QP has fully relied upon, and disclaims responsibility for, marketing information derived from a third-party expert retained by Sigma through the following document:

 

·Benchmark Mineral Intelligence, Q3 - 2022: Lithium Forecast, Q3 - 2022.

 

This information is used in Section 19, the Mineral Reserve estimate in Section 15, and the financial analysis in Section 22.

 

The QP considers it reasonable to rely on Benchmark Mineral Intelligence because the company is independent, privately owned, and is an industry leader in battery metals reporting. Benchmark Mineral Intelligence, founded in 2014, is a London-based IOSCO-regulated Price Reporting Agency and specialist information provider for the lithium-ion battery to EV supply chain. Benchmark Mineral Intelligence specialises in providing in depth market reports that give a comprehensive analysis of an individual metal or mineral market. These reports cover world supply and demand, the operations of the major producers, end-use market applications, price trends, international trade patterns and forecasts. Benchmark Mineral Intelligence also publishes regularly updated cost curves and databases for a number of metals and minerals.

 

The QP has fully relied upon, and disclaims responsibility for contract and off-take information derived from Sigma from the following document:

 

·Sigma’s announcement on October 5, 2021, of the Sigma and LG Energy Solution, Ltd. Binding Offtake Agreement Term Sheet (Term Sheet - Lithium concentrate offtake dated October 5, 2021)

 

This information is used in Section 19, and in support of the Mineral Resource estimate in Section 14, the Mineral Reserve estimate in Section 15, and the financial analysis in Section 22.

 

3.2Units and Currency

 

Système International d'unités (SI) metric units are used, including metric tonnes (tonnes, t) for weight.

 

All currency amounts are stated in US dollars (US$) unless otherwise stated.

 

3.3Environmental, Permitting and Social Licence

 

The QP has fully relied upon, and disclaims responsibility for, environmental, permitting, and social licence information derived from third-party experts retained by Sigma through the following document:

 

·Environmental Regularization Summary – Xuxa Project - DNPM 824 692 71: report prepared by Harpia Consultoria Ambiental for Sigma, 2019.

·Vetor Ambiental updated the report for the Phase 1 Project in 2020 and for Phase 2 in 2021.

 

This information is used in Section 20, and in support of the Mineral Resource estimate in Section 14, the Mineral Reserve estimate in Section 15, and the financial analysis in Section 22.

 

This Environmental Regularization Summary for Phase 1 Xuxa by Harpia Consultoria Ambiental is a translation from and is based on an Environmental Impact Assessment (EIA) prepared by NEO Soluções Ambientais, ATTO GEO Geologia e Engenheria and Vetor Ambiental and submitted by Sigma to applicable regulatory authorities.

 

Similarly, the Environmental Regularization Summary for Phase 2 Barreiro is based on an Environmental Impact Assessment (EIA) prepared by Vetor Ambiental and submitted by Sigma to applicable regulatory authorities.

 

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The EIS was comprised of:

 

·Estudo e Relatorio de Impacto Ambiental Phase 1 North Pit – EIA-RIMA dated 30 October 2018

·Plano de Controle Ambiental Phase 1 North Pit– PCA dated December 2018

·Estudo e Relatorio de Impacto Ambiental Phase 1 south pit – EIA-RIMA dated 28 August 2020, and

·Plano de Controle Ambiental Phase 1 south pit – PCA dated 28 August 2020

·Estudo e Relatorio de Impacto Ambiental Phase 2 Barreiro t – EIA-RIMA dated 20 February 2022, and

·Plano de Controle Ambiental Phase 2 Barreiro – PCA dated 15 March, 2022

 

The Phase 2 Barreiro Environmental Regularization Summary is based on an EIA-RIMA and PCA which was prepared by Vetor Ambiental.

 

This information is used in Section 20, and in support of the Mineral Resource estimate in Section 14, the Mineral Reserve estimate in Section 15, and the financial analysis in Section 22.

 

The EIA and the Environmental Regularization Summary for Phase 1 cover the licensing process for Xuxa North & South pits and waste piles 1 ,2 ,3 and 4. The EIS and the Environmental Regularization Summary for Phase 2 cover the licensing process for Barreiro pit and waste pile 1.

 

3.4Taxation

 

The QP has fully relied upon, and disclaims responsibility for taxation (including amortization, interest rates, depreciation, discounts), levy, royalty, and buy-back options information derived from third-party experts retained by Sigma including the following document:

 

·Sigma Legal Opinion – SUDENE and RECAP tax incentives: legal opinion prepared by Lefosse Advogados 25 March 2019.

·Import and Local taxes opinion was prepared by TSX Engineering December 2021

 

This information is used in Section 22, and in support of the Mineral Reserve estimate in Section 15.

 

3.5Mineral Tenure

 

The QPs have not reviewed the mineral tenure, nor independently verified the legal status, ownership of the Project area, underlying property agreements or permits.  The QPs have fully relied upon, and disclaim responsibility for, information derived from third-party experts retained by Sigma through the following document:

 

·Friere, W., Costa, B., Soarres, D.R., and Azevedo, M., 2018:  Legal Opinion 29/2018:  report prepared by William Freire and Partners for Sigma, 10 April 2018, 68 p.

 

This information is used in Section 4 of the report, and in support of the Mineral Resource estimate in Section 14, the Mineral Reserve estimate in Section 15, and the financial analysis in Section 22.

 

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4PROPERTY DESCRIPTION AND LOCATION

 

4.1Property Description and Location

 

The Project area is located within Zone SE24 of the Americas topographic map reference, and is divided into four properties:

 

·Grota do Cirilo property: UTM 190,615 m east and UTM 8146,788 m north; WGS 84, Zone 24S

·Genipapo property: UTM 191,226 m east and UTM 8,155,496 m north, WGS 84, Zone 24 K

·Santa Clara: UTM 197,682 m east and UTM 8,134,756 m north, WGS 84, Zone 24 K

·São José property: UTM 190,612 m east and UTM 8,119,190 m north, 84, Zone 24 K.

 

The property locations are shown in Figure 4-1.

 

 

Figure 4-1: Project Properties - Genipapo, Grota do Cirilo, Santa Clara and São José

 

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4.2Mineral Tenure

 

The legal framework for the development and use of mineral resources in Brazil was established by the Brazilian Federal Constitution, which was enacted on October 5, 1988 (the Brazilian Constitution) and the Brazilian mining code, which was enacted on January 29, 1940 (Decree-law 1985/40, later modified by Decree-law 227, of February 29, 1967, the Brazilian Mining Code).

 

According to the Brazilian Constitution, all mineral resources in Brazil are the property of the Federal Government. The Brazilian Constitution also guarantees mining companies the full property of the mineral products that are mined under their respective concessions. Mineral rights come under the jurisdiction of the Federal Government and mining legislation is enacted at the Federal level only. To apply for and acquire mineral rights, a company must be incorporated under Brazilian law, have its management domiciled within Brazil, and its head office and administration in Brazil.

 

In general, there are no restrictions on foreign investment in the Brazilian mining industry, except for mining companies that operate, or hold mineral rights within a 150 km-wide strip of land parallel to the Brazilian terrestrial borders. In this instance the equity interests of such companies have to be majority Brazilian-owned. Exploration and mining activities in the border zone are regulated by the Brazilian Mining Code and supporting legislation.

 

The Project consists of 25 mineral rights, mining concessions, applications for mining concessions and exploration permits covering an area of 18.424,21 ha in four property areas (refer to Figure 4-1). The tenure holdings are summarized in Table 4-1 and tenure outlines are shown in Figure 4-2. The identification numbers used in Figure 4-2 correspond to the identification numbers in the first column of Table 4-1. A summary of the types of concession within each property area is provided in Table 4-2.

 

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Table 4-1: Mineral Rights Description

 

ID Number Year Type Expiry Date Area Associated Property
(ha)
1 802.401 1972 Mining concession (*) Life of mine 1,796.5 Genipapo
2 802.400 1972 Mining concession (*) Life of mine 969.13 Genipapo
3 4.134 1953 Mining concession (*) Life of mine 494.69 Grota do Cirilo
4 831.891 2017 Exploration Permit 17/07/2023 (**) 10.57 Genipapo
5 830.039 1981 Mining Application Life of mine 715.24 Grota do Cirilo
6 824.692 1971 Mining concession Life of mine 756.21 Grota do Cirilo
7 810.345 1968 Mining concession (*) Life of mine 125.54 Grota do Cirilo
8 9.135 1967 Mining concession (*) Life of mine 312 Grota do Cirilo
9 5.804 1953 Mining concession (*) Life of mine 9.33 Grota do Cirilo
10 804.541 1971 Mining Application Life of mine 44.89 Grota do Cirilo
11 824.695 1971 Mining concession (*) Life of mine 1,069.2 Grota do Cirilo
12 805.799 1970 Mining concession (*) Life of mine 8.29 Grota do Cirilo
13 801.312 1972 Mining concession (*) Life of mine 2,505.22 Grota do Cirilo
14 831.975 2017 Exploration Permit 19/03/2023 (**) 4.03 Grota do Cirilo
15 2.998 1953 Mining concession (*) Life of mine 327.84 Santa Clara
16 801.870 1978 Mining concession Life of mine 544.9 Santa Clara
17 801.316 1972 Mining concession (*) Life of mine 3,727.9 Santa Clara
18 801.315 1972 Mining concession (*) Life of mine 991.71 Santa Clara
19 813.413 1973 Mining concession (*) Life of mine 379.31 Santa Clara
20 832.889 2013 Extension Exploration Permit 02/12/2022 (**) 810.23 São José
21 806.856 1972 Mining concession (*) Life of mine 1,920.4 São José
22 808.869 1971 Mining concession (*) Life of mine 29 São José
23 804.088 1975 Mining concession Life of mine 29.22 São José
24 801.875 1978 Mining concession Life of mine 281.51 São José
25 830.580 1979 Exploration Permit N/A*** 686.89 São José
 

 

* Mining rights covered by the Mining Group 931.021/83.

 

**Deadline for submission to the ANM of the final research report

 

  *** The Final Research Report was submitted in due time and is pending analysis. There is no provision for an administrative decision.

 

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Figure 4-2: Project Mineral Rights, North and South Complexes

 

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Table 4-2: Property Tenure Summary

 

Property

Area

(ha)

Concessions Historical Workings
Grota do Cirilo 5,919 8 mining concessions, 2 Application for mining concession, 1 exploration permit Xuxa, Barreiro, Lavra do Meio, Murial and Maxixe
São José 3,757 4 mining concessions and 2 exploration permits Samambaia, Lavra Grande, Ananias, Ramom and Lavra Antiga
Genipapo 2,776 2 mining concessions and 1 exploration permit Morundu and Lavra Velha
Santa Clara 5,971 5 mining concessions Lavra do Honorato

 

All concessions have been surveyed on the ground and have been monumented (physical boundary markers are in place). Sigma retains third-party consultants to monitor its concession obligations. The consultants report on both a monthly and a quarterly basis.

 

The following payments and fees are required to keep concessions current:

 

·ANM Proceeding 802.401/1972, 802.400/1972, 4.134/1953, 824.692/1971, 810.345/1968, 9.135/1967, 5.804/1953, 824.695/1971, 805.799/1970, 801.312/1972, 2.998/1953, 801.870/1978, 801.316/1972, 801.315/1972, 813.413/1973, 806.856/1972, 808.869/1971, 804.088/1975, 801.875/1978 (mining concessions): Financial Compensation for the Exploration of Mineral Resources (CFEM) will only be due when there is mineral production in the areas. For the sale of lithium, the value of CFEM is equivalent to 2% of gross sales revenue, less taxes levied on its sale

·ANM Proceeding 830.039/1981, 804.541/1971 (Mining Application): there is no periodic payment due

·ANM Proceeding 850.580/1979 (Exploration permit with Final report delivered): there is no periodic payment due

·ANM Proceeding 832.889/2013, (Extension Exploration Permit): The annual payments due at the annual fees per hectare (TAH) were made, totaling the amount of R$4,318.54 (about $US827)

·ANM Process 831.891 / 2017, 831.975 / 2017, (Original Exploration Permit): The annual payments due at the annual fees per hectare (TAH) were made, totaling the amount of R$ 51.83 (about $US9.80)

·The TAH is due in January, for permits granted from July to December of the previous year, and in July, for permits granted from January to June of the present year. Currently the TAH is R$3.55/hectare for original exploration permits and R$5.33/hectare for renewed exploration permits

 

Sigma has seven mining concessions that have had Economic Exploitation Plan (Plano de Aproveitamento Econômico - PAE) approved, covering the Xuxa, Barreiro, Lavra do Meio, Murial, Maxixe and Nezinho do Chicâo deposits within the Grota do Cirilo property.

 

4.3Surface Rights

 

Under Brazilian laws, foreign entities may not own a controlling interest in surface rights. The surface rights in the Grota do Cirilo area, the current primary focus of activity, are held by two companies, Arqueana Minérios e Metais (Arqueana) and Miazga Participações S.A. (Miazga) and certain areas are held under private ownership. The controlling interest in Sigma, the A10 Investment Fund, is also the controlling interest in Arqueana and Miazga. Through these affiliations with Sigma, landowner agreements have been negotiated with these entities to support Sigma’s exploration and development activities within the Grota do Cirilo property. As required for reconnaissance exploration purposes, Sigma has negotiated exploration access in the remaining property areas.

 

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4.4Agreements

 

SMSA has entered into two rights-of-way agreements with Arqueana and Miazga. There are no conditions attached to the agreements.

 

4.5Royalties and Encumbrances

 

4.5.1CFEM Royalty

 

The Brazilian Government is entitled to a Compensação Financeira pela Exploração de Recursos Minerais (CFEM) royalty. The holder of a mining concession for lithium mineral must pay the Brazilian government 2.0% of the gross income from the sale thereof. The only deductions allowed are taxes levied on commercial sales.

 

4.5.2Royalty Agreements

 

There are two net smelter return (NSR) royalties.

 

The first provides for a net smelter return, calculated at the rate of 1% over the gross revenues of SMSA, less all taxes and costs incurred in the process of extraction, production, processing, treatment, transportation and commercialization of the products sold. SMSA has a purchase option, exercisable anytime, for the price of US$3,800.000. The royalty has a sales option, for the same price, exercisable as follows:

 

·When SMSA enters into commercial production and has reached a threshold of 40,000 t of mineral products concentrates per year; or

 

·The original controlling group ceases to have more than 30% of SMSA. The “original controlling group” reference is to the A10 Investment Fund that currently controls Sigma.

 

The second royalty provides for an NSR royalty calculated at the rate of 1%, over the gross revenues of SMSA, less all taxes and royalties payable to government authorities, any discounts or sales commissions paid, and any insurance or freight cost borne by SMSA. There is no buyout provision for this royalty.

 

Sigma intends to exercise its buyback option on the first NSR royalty in its first year of commercial production at the Project.

 

4.6QP Comment

 

To the extent known, there are no other significant factors and risks that may affect access, title, or the right or ability to perform work on the Project that have not been discussed in this Report.

 

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5ACCESSIBILITY, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND PHYSIOGRAPHY

 

5.1Accessibility

 

The Project is located in northeastern Minas Gerais State, in the Municipalities of Itinga and Araçuaí, approximately 25 km east of the town of Araçuaí and 450 km northeast of Belo Horizonte.

 

The Project is well served by a public and private road network, as a result of its proximity to National Road 367. The Project is accessible year-round by a network of arterial and back country service roads.

 

National route BR 251 accesses the Port of Vitoria in the State of Espirito Santo, some 700 km from the Project site. This port could represent a potential port of export for any spodumene production from the Project. The national road BR116 and BR415 accesses to Ilhéus Port which is 540km from the project and is also an option for Sigma.

 

5.2Climate

 

The region is characterized by a dry, semi-arid and hot climate. It has a temperature mean of 24.5ºC and a low annual average rainfall of 750 mm. There is a pronounced dry season with the driest month being June. The wettest month is November. There is no cold season.

 

Exploration activities are currently conducted year-round. It is expected that any future mining activities will also be year-round.

 

5.3Local Resources and Infrastructure

 

When Sigma purchased Arqueana Minérios e Metais Arqueana (Arqueana; see discussion in Section 6), had been in operation since the 1970s. In common with many brownfield projects, the Grota do Cirilo property has substantial infrastructure constructed to support mining activities. This includes provision of power supply and a site power substation, an extensive office block equipped with internet and telephones, accommodation for 40 persons on site, dining hall and kitchen, workshop, on-site laboratory and sample storage building, warehouse, core storage, a fuel storage facility with pumping equipment, and a water pumping facility from the Jequitinhonha River with its own reservoir. The main 138kV transmission line from the Irape hydro power station runs through the northern part of the Project area. Figure 5-1 is an aerial photograph showing the infrastructure in the pilot plant/office site area. The Project main office is shown in Figure 5-2. Figure 5-3 is a photograph showing the layout of the original 2014 Sigma pilot plant. Figure 5-4 shows the current pilot plant layout.

 

Additional information on the infrastructure envisaged is provided in Section 18.

 

The nearest larger communities are Itinga and Araçuaí with populations of 14,000 and 40,000 respectively. Araçuaí is serviced by the local municipal airport and by mobile phone network from the principal Brazilian service providers. The closest major domestic airport is located at Montes Claros, 327 km west of Araçuaí.

 

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Figure 5-1: Aerial View, Current Project Infrastructure

 

Note: Drone view, flight dated September 2018, image looks northeast, photographic still image by Sigma. The core storage facility (labelled 2 on the image) provides a scale indicator and is about 30 m wide and 45 m long. Due to the elevated perspective view, no other reliable scale indicator can be provided. The infrastructure is located in the tenure numbered “3” in Figure 4-2 and Table 4-2.

 

 

Figure 5-2: Field Office (location 6 in Figure 5-2)

 

Note: Drone view, flight dated September 2018, image looks east, photographic still image by Sigma. Vehicles provide scale indicator. Due to the elevated perspective view, no other reliable scale indicator can be provided.

 

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Figure 5-3: SMSA Pilot Plant

 

Note: Photograph taken by Sigma, 2014. Images shows the heavy mineral pilot plant in operation. At the time, the plant was processing material to recover tantalite and cassiterite. It consisted of a 10 tonne per hour water pulse jig (the green structure), two crushers, a jaw crusher and roll crusher.

 

 

Figure 5-4: Lithium Metallurgical Test Phase Production Plant

 

Note: Drone view, flight dated September 2018, image looking east–southeast, photographic still image by Sigma. The core storage facility (silver roof at top right of image) provides a scale indicator and is about 30 m wide and 45 m long. Due to the elevated perspective view, no other reliable scale indicator can be provided.

 

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5.4Physiography

 

The Project topography consists of gently rolling hills with less than 100 m difference in elevation. The hilltops are covered with a veneer of alluvium, up to 5 m thick, which is not present on the hill slopes where bedrock is frequently exposed.

 

The Jequitinhonha River and the Araçuaí River join west of the Project and the Jequitinhonha River passes through the Grota do Cirilo property in close proximity to the Sigma offices, as shown in Figure 5-1.

 

The Project area is characterized by thick thorn scrub and trees of medium height - except where it has been cleared for agriculture. The natural vegetation on the hilltops is typical of savannah grassland (Figure 5-5).

 

 

Figure 5-5: Photo Showing Typical Vegetation Within Project Area

 

Note: The photograph looks north. The image is taken in the licence labelled as “6” in Table 4-2 and
Figure 4-2. Due to the photographic perspective view, no reliable scale indicator can be provided.

 

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6HISTORY

 

6.1Project History

 

The exploration history for the Project is summarized in Table 6-1.

 

Table 6-1: Project History

 

Operator Year Comment
Companhia Estanìfera do Brazil (CEBRAS) 1957 –1980s Tin production consisting of a, cassiterite/tantalite concentrate with by-products of feldspar and lithium minerals.  Mining focused on near surface, weathered zones, excavations ranged from 100–700 m in length.  CEBRAS operated a gravity separation plant, consisting of a jaw crusher, a trommel and cone crusher, with sizing screens and jigs to recover tantalite/cassiterite concentrate.  Feldspar and the lithium minerals, spodumene, lepidolite, amblygonite and petalite, were handpicked before the jaw crusher.
Arqueana Minérios e Metais (Arqueana) 1980s –2000s Produced a 6–6.5%% Li2O spodumene concentrate and a 3.5-4% Li2O petalite concentrate.  No systematic exploration was conducted.  Historic mining occurred primarily where the bedrock had been exposed by erosion, on hill flanks.  Following the death of the owner of Arqueana, artisan-level operations continued.  The focus was on feldspar, petalite, ornamental-grade tourmaline and quartz. This was further reduced, after some years, to the underground mining of minor amounts of tantalite and gemstone.
Tanex Resources plc (Tanex; a subsidiary of Sons of Gwalia Ltd (Sons of Gwalia) 2000 –2003 Channel sampling, air-track drilling, 13 reverse circulation (RC) drill holes.  Based on a report that has no location maps, it appears that Tanex and Sons of Gwalia drilled two drill holes at Lavra do Meio in 2000.  No other mentions of drill hole locations have been found.  In addition, Sigma has not been able to locate or any of the collar locations for the Tanex and Sons of Gwalia drilling on the ground.
Arqueana 2003 –2012 Local workers continue production, but at a reduced rate.
RI-X 2012 Acquires a controlling interest in Arqueana, incorporates SMSA.  
Sigma 2012 to date Completes mapping, data compilation, ground magnetic survey, channel sampling.  Drill program in 2014 of 984m to initially investigate the Xuxa and Barreiro prospects.  Heavy mineral separation (HMS) pilot plant constructed in 2014–2015, consisting of a jaw crusher, roll crusher, sizing screen and pulse jig.  Acquired a dense media pilot plant in 2017 to produce lithium concentrate.  Completed drill program of 255 holes (approx. 42,310 m) in the Grota do Cirilo property area, on the Xuxa, Barreiro, Lavra do Meio, Maxixe and Murial prospects.  An internal Mineral Resource estimate was completed at Xuxa, Barreiro, Murial and Lavra do Meio.  The first public disclosure of a Mineral Resource estimate for Grota de Cirilo was in 2017 which was only for the Xuxa deposit. Updated resources for Xuxa and first-time estimate of Mineral Resources for Barreiro, Lavra do Meio and Murial were released in January 2019. A feasibility study for Xuxa was issued on the 18th of October 2019 with the Phase 1 mineral reserve statement. A pre-feasibility study for Phase 2 Barreiro was completed in February 2022 and a prefeasibility study for phase 3 at Nezinho do Chicão (NDC) was completed  in October 2022. A Front-End Engineering Design  (FEED) was completed at Xuxa Phase 1, in October 2020 and construction was immediately commenced thereafter. The construction is around 70% complete at the effective date of the report .

 

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