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 May 2022

 

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, Phase 1 DFS and Phase 2 PFS Update of the NI 43-101 Technical Report, dated May 25, 2022
99.2   Consent of  Homero Delboni Jr.
99.3   Consent of Jarrett Quinn
99.4   Consent of Brian Talbot
99.5   Consent of Marc-Antoine Laporte
99.6   Consent of Porfirio Cabaleiro Rodriguez

 

 

 

 

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: May 25, 2022 Shape

Description automatically generated with low confidence
  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

 

Phase 1 DFS and Phase 2 PFS update of the NI 43-101 TECHNICAL REPORT

 

Prepared for: Sigma Lithium Corporation

 

Prepared by:

 

Homero Delboni Jr., MAusIMM, Promon Engenharia

 

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

 

Jarrett Quinn, P.Eng., Primero Group Americas

 

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

 

Brian Talbot, FAusIMM, Rtek Pty Ltd.

 

Effective Date: 24th February 2022

 

Issue Date: 25th May 2022

 

   

 

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IMPORTANT NOTICE

 

This report was prepared as National Instrument 43-101 Technical Report for Sigma Lithium Corporation (Sigma) by Primero Group Americas Inc. (a subsidiary of Primero Group Ltd), SGS Geological Services, GE21 Consultoria Mineral and Promon Engenharia Ltda. (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.  Except for the purpose legislated under Canadian provincial and territorial securities law, any other use of this report by any third party is at that party’s sole risk.

 

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Table of Contents

 

1 SUMMARY 24

 

1.1 Introduction 24
1.2 Property Description and Location 24
1.3 Accessibility, Climate, Local Resources,Infrastructure and Physiography 25
1.4 History 25
1.5 Geological Setting and Mineralization 26
1.6 Exploration 26
1.7 Drilling 27
1.8 Sample Preparation, Analyses and Security 27
1.9 Data Verification 29
1.10 Mineral Processing and Metallurgical Testing 30
1.11 Mineral Resource Estimates 31
1.12 Mineral Reserve Estimates 35
1.13 Mining Methods 38
1.14 Recovery Methods 39
1.15 Project Infrastructure 39
1.16 Market Studies and Contracts 41
1.17 Environmental Studies, Permitting and Social or Community Impact 42
1.18 Capital and Operating Costs 45
1.19 Economic Analysis 47
1.20 Interpretation and Conclusions 51
1.21 Recommendations 52

 

2 INTRODUCTION 54

 

2.1 Terms of Reference 54
2.2 Effective Dates 55
2.3 Qualified Persons 55
2.4 Site Visits 55
2.5 Information Source 56

 

3 RELIANCE ON OTHER EXPERTS 57

 

3.1 Marketing 57
3.2 Units and Currency 57
3.3 Environmental, Permitting and Social Licence 57
3.4 Taxation 58
3.5 Mineral Tenure 58

 

4 PROPERTY DESCRIPTION AND LOCATION 59

 

4.1 Property Description and Location 59
4.2 Mineral Tenure 60
4.3 Surface Rights 63
4.4 Agreements 64
4.5 Royalties and Encumbrances 64
4.6 QP Comment 64

 

5 ACCESSIBILITY, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND PHYSIOGRAPHY 65

 

5.1 Accessibility 65
5.2 Climate 65
5.3 Local Resources and Infrastructure 65
5.4 Physiography 68

 

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6 HISTORY 69

 

6.1 Project History 69
6.2 Production 69

 

7 GEOLOGICAL SETTING AND MINERALIZATION 71

 

7.1 Regional Geology 71
7.2 Local Geology 71
7.3 Property Geology 74

 

8 DEPOSIT TYPES 84

 

9 EXPLORATION 86

 

9.1 Introduction 86
9.2 Grids and Surveys 86
9.3 Geological Mapping 86
9.4 Channel Mapping 86
9.5 Trench Sampling 88
9.6 Exploration Potential 89

 

10 DRILLING 93

 

10.1 Introduction 93
10.2 Drill Type 93
10.3 Sigma Drilling Campaigns 93
10.4 Drill Hole Logging 103
10.5 Recovery 104
10.6 Drill Surveys 104
10.7 QP Comment 104

 

11 SAMPLE PREPARATION, ANALYSES AND SECURITY 105

 

11.1 Introduction 105
11.2 Sampling 105
11.3 Density Determinations 106
11.4 Analytical and Test Laboratories 107
11.5 Sample Preparation and Analysis 107
11.6 Quality Assurance and Quality Control 108
11.7 Sample Security 122
11.8 Sample Storage 122
11.9 QP Comments 122

 

12 DATA VERIFICATION 124

 

12.1 Drilling Database 124
12.2 Witness Sampling 124
12.3 QP Comments 128

 

13 MINERAL PROCESSING AND METALLURGICAL TESTING 129

 

13.1 Xuxa Metallurgical Test work (2018-19) 129
13.2 Xuxa Metallurgical Test Work (2020-2021) 138
13.3 Barreiro Metallurgical Test Work (2020-21) 156

 

14 MINERAL RESOURCE ESTIMATES 172

 

14.1 Xuxa Deposit 172
14.2 Barreiro Deposit 182
14.3 Murial Deposit 194
14.4 Lavra Do Meio Deposit 202

 

15 MINERAL RESERVE ESTIMATES 213

 

15.1 Xuxa Mineral Reserves 213
15.2 Xuxa Pit Optimization Parameters 214

 

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15.3 Xuxa Modifying Factors 217
15.4 Xuxa Pit Optimization Study 222
15.5 Xuxa Mineral Reserves Statement 228
15.6 Barreiro Mineral Reserves 229
15.7 Barreiro Pit Optimization Parameters 230
15.8 Barreiro Modifying Factors 233
15.9 Barreiro Pit Optimization Study 237
15.10 Barreiro Mineral Reserves Statement 242

 

16 MINING METHODS 243

 

16.1 Xuxa Open Pit Mining 243
16.2 Xuxa Mine Sequencing 254
16.3 Xuxa Mine Fleet 262
16.4 Barreiro Open Pit Mining 282
16.5 Barreiro Mine Sequencing 299
16.6 Barreiro Mine Fleet 305

 

17 RECOVERY METHODS 324

 

17.1 Processing Overview 324
17.2 Xuxa Front-End Engineering Design (FEED) Update 324
17.3 Xuxa Process Plant 325
17.4 Barreiro Process Plant 334

 

18 Project Infrastructure 341

 

18.2 Roads 341
18.3 Earthworks and Buried Services 343
18.4 Water Balance (Storm Water, Water Treatment) xuxa 344
18.5 Sewage 345
18.6 Built Infrastructure 348
18.7 Stockpiles 348
18.8 Waste Disposal 351
18.9 Fuel 352
18.10 Power Supply 362
18.11 Water Supply 361
18.12 Compressed Air 363
18.13 Control Systems 363
18.14 Communication Systems 363
18.15 Camps and Accommodation 364
18.16 Port Facilities 364

 

19 MARKET STUDIES AND CONTRACTS 364

 

19.1 Lithium Demand Forecast 366
19.2 Lithium Supply Forecast 367
19.3 Lithium Price Forecast 370
19.4 Contracts and Off-Take Agreements 371

 

20 ENVIRONMENTAL STUDIES, PERMITTING AND SOCIAL OR COMMUNITY IMPACT 374

 

20.1 Environmental Considerations 374
20.2 Permitting Considerations 378
20.3 Social Considerations 380
20.4 Evaluation of Environmental Impacts and Mitigation Actions 382
20.5 Waste and Water Management 384
20.6 Relations with Stakeholders 385
20.7 Rehabilitation and Closure Planning 386

 

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20.8 Phase 2 Barreiro Pegmatite Environmental Work 387

 

21 Capital and Operating Costs – Xuxa (Phase 1) and Barreiro (Phase 2) 398

 

21.1 Basis of Estimate 398
21.2 Work Breakdown Structure 398
21.3 Estimate Plan 398
21.4 Capital Cost 400
21.5 Operating Costs 412

 

22 ECONOMIC ANALYSIS 420

 

22.1 Economic Assumptions 420
22.2 Phase 1 DFS Economic Analysis 422
22.3 Phase 2 PFS Economic Analysis 431
22.4 Phase 1 + Phase 2 PFS Economic Analysis 440

 

23 ADJACENT PROPERTIES 450

 

24 OTHER RELEVANT DATA AND INFORMATION 451

 

24.1 Schedule for Xuxa Phase 1 451
24.2 Schedule for Barreiro Phase 2 452
24.3 Project Execution Plan 452

 

25 INTERPRETATION AND CONCLUSIONS 455

 

25.1 Conclusions 455
25.2 Risk Evaluation 459
25.3 Opportunities 460

 

26 RECOMMENDATIONS 461

 

26.1 Geology and Resources 461
26.2 Xuxa 461
26.3 Barreiro Project Recommendations 462

 

27 REFERENCES 463

 

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List of Tables

 

Table 1-1 – Xuxa Deposit Mineral Resource Estimate 33
Table 1-2 – Barreiro Deposit Mineral Resource Estimate 33
Table 1-3 – Murial Deposit Mineral Resource Estimate 34
Table 1-4 – Lavra do Meio Deposit Mineral Resource Estimate 34
Table 1-5 – Parameters Used in Xuxa Pit Optimization 35
Table 1-6 – Xuxa Mineral Reserves 36
Table 1-7: Parameters Used in Barreiro Pit Optimization 37
Table 1-8: Barreiro Mineral Reserves 38
Table 1-9 – Xuxa Waste Pile Storage 40
Table 1-10: Barreiro Waste Pile Storage 40
Table 1-11 – Capital Cost Estimate Summary Xuxa 45
Table 1-12: Capital Cost Estimate Summary Barreiro 46
Table 1-13: Xuxa Operating Cost Estimate Summary 46
Table 1-14: Barreiro Operating Cost Estimate Summary 47
Table 1-15 – Base Case After-Tax NPVs 47
Table 1-16: Phase 1 Base Case Scenario Results 48
Table 1-17: Key Phase 1 Technical Assumptions 48
Table 1-18: Phase 2 Base Case Scenario Results 49
Table 1-19: Key Phase 2 Technical Assumptions 50
Table 1-20: Phase 1+2 Base Case Scenario Results 50
Table 1-21: Key Phase 1+2 Technical Assumptions 51
Table 4-1 – Mineral Rights Description 61
Table 4-2 – Property Tenure Summary 63
Table 6-1 – Project History 69
Table 9-1 – Channel Sampling Summary 87
Table 9-2 – Grota do Cirilo Trench Sampling Summary 88
Table 9-3 – Grota do Cirilo Property Prospects 89
Table 9-4 – Genipapo Property Prospects 91
Table 9-5 – Santa Clara Property Prospects 92
Table 10-1 – Total Sigma Drill Holes to December 31, 2021 93
Table 10-2 – Total Xuxa Drilling 93
Table 10-3 – Xuxa Example Drill Intercept Table 94
Table 10-4 – Total Barreiro Drilling 95
Table 10-5 – Barreiro Example Drill Intercept Table 96
Table 10-6 – Total Lavra do Meio Drilling 97
Table 10-7 – Lavra do Meio Example Drill Intercept Table 98
Table 10-8 – Total Murial Drilling 99
Table 10-9 – Murial Example Drill Intercept Table 99
Table 10-10 – Nezinho do Chicao Drilling to December 1, 2021 101
Table 10-11 – Nezinho do Chicao Example Drill Intercept Table 101
Table 10-12 – Total Maxixe Drilling 102
Table 11-1 – Specific Gravity of Lithium-Bearing Pegmatites 106
Table 11-2 – Standard Average Li Values with Analytical Error 108
Table 11-3: Check Assay Original vs Control Samples 114
Table 11-4: Check Assay Original and Control Descriptive Statistics 114
Table 11-5: Standard Average Li Values with Analytical Error 115
Table 12-1 – Witness Sample Mineralized Interval Comparison between SGS Geosol and SGS Lakefield 125
Table 12-2 – Witness Sample Original vs Control Differences 126
Table 12-3 – Witness Sample Original and Control Descriptive Statistics 126

 

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Table 13-1 – Chemical Analysis and WRA Results 131
Table 13-2 – Bond Abrasion and Ball Mill Work Index Test Work Summary 131
Table 13-3 – Average UCS and CWi 132
Table 13-4 – Summary of Ore Sorter Test work Results 132
Table 13-5 – Summary of HLS Test Results on Variability Samples 133
Table 13-6 – Coarse Fraction DMS results 134
Table 13-7: DMS Tailings Grades 134
Table 13-8 – Fines Fraction DMS 2nd Pass SG Cut-Points 135
Table 13-9 – Ultra-fine Fraction DMS Results 136
Table 13-10: Variability sample assays 141
Table 13-11: Semi-quantitative XRD analysis of the variability samples 141
Table 13-12: HLS Interpolated stage and global lithium recoveries (6% Li2O concentrate) for each variability sample 142
Table 13-13: Variability Sample 2 Global HLS Results 143
Table 13-14: Variability Sample 3 Global HLS Results 143
Table 13-15: Variability Sample 6 Global HLS Results 144
Table 13-16: Variability Sample 6 Global HLS Results with magnetic separation 144
Table 13-17: DMS and magnetic separation results by size fraction 145
Table 13-18: Var 2 Combined DMS stage results 146
Table 13-19: Var 3 Combined DMS stage results 146
Table 13-20: Var 6 Combined DMS stage results 147
Table 13-21: Var 2 Combined Global DMS results 149
Table 13-22: Var 3 Combined Global DMS results 149
Table 13-23: Var 6 Combined Global DMS results 150
Table 13-24: Summary of 2019 and 2021 DMS and magnetic separation concentrate grade and global recovery (including hypofines fraction) 151
Table 13-25: Estimates of DMS Circuit Recovery 151
Table 13-26: Summary of Global Recovery and Yield at 5.5% Li2O for 9.5 mm Top Size 156
Table 13-27 – Description of Barreiro Variability Samples 158
Table 13-28 – Variability Sample and Composite Sample Assays 158
Table 13-29 – Semi-quantitative XRD analysis of the four variability samples and the composite sample 159
Table 13-30 – Estimates of Lithium Deportment to Spodumene 159
Table 13-31 – HLS Interpolated stage and global lithium recoveries (6% Li2O concentrate) for each crush size 161
Table 13-32 – Semi-Quantitative XRD Analysis for Selected Samples (-10 mm crush size) 163
Table 13-33 – HLS Interpolated Stage and Global Combined Lithium Recoveries (6% Li2O concentrate) for each Variability Sample 163
Table 13-34 – Variability Sample 1 Global HLS Results 164
Table 13-35 – Variability Sample 2 Global HLS Results 164
Table 13-36 – Variability Sample 3 Global HLS Results 165
Table 13-37 – Variability Sample 4 Global HLS Results 165
Table 13-38 – Coarse fraction DMS stage results 167
Table 13-39 – Fines fraction DMS stage results 167
Table 13-40 – Ultrafines fraction DMS stage results 167
Table 13-41 – Global DMS results by size fraction 169
Table 13-42 – Global combined DMS results 169
Table 13-43 – Global combined DMS results with middlings re-crush 169
Table 13-44 – Summary of DMS concentrate grade and recovery 170
Table 13-45 – DMS concentrate semi-quantitative XRD analysis 170
Table 13-46: Barreiro Global Recovery and Yield between 6% and 5.5% Li2O Product Grade 171
Table 14-1 – Xuxa Assay Statistics Inside Mineralized Solids 173

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Table 14-2 – Xuxa 1 m Composite Statistics 174
Table 14-3 – Xuxa Resource Block Model Parameters 176
Table 14-4 – Xuxa Parameters for Reasonable Prospects for Eventual Economic Extraction 181
Table 14-5 – Xuxa Deposit Mineral Resource Estimate 181
Table 14-6 – Barreiro Assay Statistics Inside Mineralized Solids 184
Table 14-7 – Barreiro 1 m Composite Statistics 184
Table 14-8 – Barreiro Resource Block Model Parameters 186
Table 14-9 – Barreiro Pit Optimization Parameters 192
Table 14-10 – Barreiro Deposit Mineral Resource Estimate 193
Table 14-11 – Murial Assay Statistics Inside Mineralized Solids 194
Table 14-12 – Murial 1 m Composite Statistics 195
Table 14-13 – Murial Resource Block Model Parameters 197
Table 14-14 – Murial Parameters for Reasonable Prospect for Eventual Economic Extraction 201
Table 14-15 – Murial Deposit Mineral Resource Estimate 201
Table 14-16 – Lavra do Meio Assay Statistics Inside Mineralized Solids 204
Table 14-17 – Lavra do Meio 1 m Composite Statistics 204
Table 14-18 – Lavra do Meio Resource Block Model Parameters 206
Table 14-19 – Lavro do Meio Parameters for Reasonable Prospect for Eventual Economic Extraction 211
Table 14-20 – Lavra do Meio Deposit Mineral Resource Estimate 211
Table 15-1: Technical and Economic Parameters Used in the Final Xuxa Pit Optimization 215
Table 15-2: Xuxa Geotechnical Pit Slope Design Criteria 216
Table 15-3: Mining Recovery Versus Partial Percentage on Block Height 219
Table 15-4: Xuxa Pit Optimization Results 223
Table 15-5: Xuxa Open Pit Operational Design Parameters 225
Table 15-6: Xuxa Pit Final Optimization Ore and Waste 226
Table 15-7: Xuxa Mineral Reserves 228
Table 15-8: Technical and Economic Parameters Used in the Final Barreiro Pit Optimization 230
Table 15-9: Barreiro Geotechnical Pit Slope Design Criteria 232
Table 15-10: Barreiro Dilution Analysis 236
Table 15-11: Barreiro Nested Pit Optimization Results 238
Table 15-12: Barreiro Open Pit Operational Design Parameters 239
Table 15-13: Barreiro Pit Final Optimization Ore and Waste 241
Table 15-14: Barreiro Mineral Reserves 242
Table 16-1: Xuxa Geotechnical Slope Results Designed Pit 245
Table 16-2: Xuxa Piezometer Locations and Results 249
Table 16-3: Variation of Hydraulic Conductivity and Storage According to Depth 251
Table 16-4: Comparison between Calculated and Adopted Values of K 251
Table 16-5: Calibration Parameters for Calculated vs Observed Head Values 252
Table 16-6: Xuxa Water Levels Reached in the Drawdown Numerical Model Simulation 253
Table 16-7: Simulated Dewatering Streamflow (Annual Average) 253
Table 16-8: Xuxa Designed Mine Sequencing 255
Table 16-9: Xuxa Non-Designed Mine Sequencing 256
Table 16-10: List of Main Equipment to be used in the Operation of the Xuxa Pits 264
Table 16-11: Drilling Equipment for Xuxa Pits 265
Table 16-12: Xuxa Staffing Requirement Summary 268
Table 16-13: Xuxa Preliminary Drill and Blast Plan - Ore 273
Table 16-14: Xuxa Preliminary Drill and Blast Plan – Waste, Soil and Saprolite - Weathered 274
Table 16-15: Xuxa Preliminary Drill and Blast Plan – Waste - Fresh 275
Table 16-16: Xuxa Recommended Drill and Blast Rigs 276
Table 16-17: Xuxa Preliminary Calculations for Drilling Requirements 277
Table 16-18: Xuxa Estimated Annual Consumption of Explosives - Ore 279

 

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Table 16-19: Xuxa Estimated Annual Consumption of Explosives - Waste 280
Table 16-20: Xuxa Estimated Annual Consumption of Explosives – Combined Ore and Waste 281
Table 16-21: Uniaxial Compression Test (UCS) Results Barreiro Pit 284
Table 16-22: Direct Shear Test Results Barreiro Pit 285
Table 16-23: Barreiro Slope Stability Analysis 289
Table 16-24: Barreiro Recommended Pit Slope Geometry 293
Table 16-25: Survey results of groundwater levels in Barreiro exploration drillholes 296
Table 16-26: Depth values of saprolite-fresh rock boundary Barreiro drill holes 297
Table 16-27: Average climatic data for Araçuaí (1981-2010) 299
Table 16-28: Barreiro Designed Mine Sequence 300
Table 16-29: Barreiro Schedule of Primary Mining Equipment 306
Table 16-30: Ore and Waste Production and percentage of material to be blasted Barreiro Pit 307
Table 16-31: Drilling Equipment for Barreiro Pit 308
Table 16-32: Barreiro Staffing Schedule 311
Table 16-33: Barreiro Preliminary Drill and Blast Plan - Ore 317
Table 16-34: Barreiro Preliminary Drill and Blast Plan – Waste 318
Table 16-35: Barreiro Recommended Drill Rig 319
Table 16-36: Barreiro Preliminary Calculations for Drilling Requirements 320
Table 16-37: Barreiro Estimated Annual Consumption of Explosives - Ore 322
Table 16-38: Barreiro Estimated Annual Consumption of Explosives - Waste 322
Table 17-1 – Xuxa Operating Parameters 331
Table 17-2: Xuxa Design Basis and Mass Balance Summary 332
Table 17-3: Xuxa Operating Hours for Main Facilities 333
Table 17-4: Barreiro Operating Parameters 338
Table 17-5: Barreiro Design Basis and Mass Balance Summary 338
Table 18-1 – Infrastructure Summary Table 349
Table 18-2 – Infrastructure Summary Table 350
Table 18-3: Xuxa Waste Pile Parameters for Stability Analysis 356
Table 18-4: Safety Factor from Xuxa Waste Pile Stability Analysis 356
Table 18-5: Xuxa Waste Pile Design Parameters 357
Table 18-6: Xuxa Waste Pile Capacities and Surfaces Areas 358
Table 18-7: Barreiro Waste Pile Design Parameters 359
Table 18-8: Barreiro Waste Pile Capacity and Surface Area 359
Table 18-9 – Total Process Plant Power Demand 362
Table 19-1: Delivery Schedule Under the LGES Offtake 371
Table 20-1 – Granted Licences and Leases 375
Table 20-2 – Baseline Studies 376
Table 20-3 – Applicable Environmental Compensation 378
Table 20-4 – Environmental Impact Minimization Measures 382
Table 20-5 – Environmental Impact Minimization Measures 387
Table 21-1 – Quoted Currency Exchange Rates 400
Table 21-2 – Xuxa Concentrator Capital Cost Estimate Summary 401
Table 21-3 Barreiro Concentrator Capital Cost Estimate Summary 404
Table 21-4: Process Plant Material Quantity Summary 407
Table 21-5: Capital Cost Estimate Basis – Process Plant 407
Table 21-6 – Contingency Requirements 409
Table 21-7 – Summary of Tax applied to the CAPEX 410
Table 21-8 – Xuxa Estimated Capital Mining Cost 412
Table 21-9: Barreiro Estimated Capital Mining Cost 412
Table 21-10: Xuxa Concentrator OPEX Processing Cost Summary 413
Table 21-11: Barreiro Concentrator OPEX Processing Cost Summary 413

 

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Table 21-12: Xuxa Processing Plant OPEX Cost Summary Breakdown 413
Table 21-13: Barreiro Processing Plant OPEX Cost Summary Breakdown 414
Table 21-14: Labour Summary 415
Table 21-15: Xuxa Mining OPEX Costs 418
Table 21-16: Barreiro Mining OPEX Costs 419
Table 22-1 – Base Case After-Tax NPVs 420
Table 22-2: Phase 1 Base Case Scenario Results 422
Table 22-3: Key Phase 1 Technical Assumptions 422
Table 22-4: Phase 1 Estimated Revenue and Operating Costs 424
Table 22-5: Phase 2 Base Case Scenario Results 431
Table 22-6: Key Phase 2 Technical Assumptions 431
Table 22-7: Phase 2 Estimated Revenue and Operating Costs 433
Table 22-8: Phase 1+2 Base Case Scenario Results 440
Table 22-9: Key Phase 1+2 Technical Assumptions 440
Table 22-10: Phase 1+2 Estimated Revenue and Operating Costs 442
Table 24-1 – Major Contracts List 453
Table 25-1 – CAPEX Summary Xuxa 458
Table 25-2: CAPEX Summary Barreiro 458
Table 25-3 – Xuxa Operating Cost Estimate Summary 459
Table 25-4: Barreiro Operating Cost Estimate Summary 459

 

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List of Figures

 

Figure 2-1 – Project Location 54
Figure 4-1 – Project Properties - Genipapo, Grota do Cirilo, Santa Clara and São José 59
Figure 4-2 – Project Mineral Rights, North and South Complexes 62
Figure 5-1 – Aerial View, Current Project Infrastructure 66
Figure 5-2 – Field Office (location 6 in Figure 5-2) 66
Figure 5-3 – SMSA Pilot Plant 67
Figure 5-4 – Lithium Metallurgical Test Phase Production Plant 67
Figure 5-5 – Photo Showing Typical Vegetation Within Project Area 68
Figure 7-1 – Regional Geologic Map (after Pedrosa-Soares et al., 2001) 72
Figure 7-2 – Local Geology Map, Northern Complex 73
Figure 7-3 – Historic Workings and Pegmatite Dike Swarms within Grota Do Cirilo Property 74
Figure 7-4 – Xuxa Cross Section (looking northeast) 75
Figure 7-5 – Barreiro Cross Section (looking northeast) 76
Figure 7-6 – Lavra do Meio Cross Section (looking north) 77
Figure 7-7 – Nezinho Do Chicao Cross Section (looking northeast) 78
Figure 7-8 – Murial Cross Section (looking north) 79
Figure 7-9 – Historical Workings within São José Property 80
Figure 7-10 – Macro Crystals at Lavra Ramon 81
Figure 7-11 – Samambaia Plan Map 82
Figure 7-12 – Ananias Plan Map 83
Figure 8-1 – Generalized Schematic Representation LCT Pegmatite 85
Figure 9-1 – Grota do Cirilo Satellite Image 87
Figure 9-2 – Channel Samples at Murial Mine 88
Figure 10-1 – Plan View of the Drilling at Xuxa 94
Figure 10-2 – Longitudinal View of the Drilling at Xuxa 95
Figure 10-3 – Plan View of the Drilling at Barreiro 96
Figure 10-4 – Longitudinal View of the Drilling at Barreiro 97
Figure 10-5 – Plan View of the Drilling at Lavra do Meio 98
Figure 10-6 – Longitudinal View of the Drilling at Lavra do Meio 98
Figure 10-7 – Plan View of the Drilling at Murial 100
Figure 10-8 – Longitudinal View of the Drilling at Murial 100
Figure 10-9 – Plan View of the Drilling at Nezinho do Chicao 101
Figure 10-10: Longitudinal View of the Drilling at Nezinho do Chicao 102
Figure 10-11 – Maxixe Drill Hole Location Plan 103
Figure 11-1 – Standard Sample Analysis Results for the 2017–2018 Batch with Standard AMIS0338 109
Figure 11-2 – Standard Sample Analyses Results for the 2017–2018 Batch with Standard AMIS0339 109
Figure 11-3 – Standard Sample Analyses Results for the 2017–2018 Batch with Standard AMIS0341 110
Figure 11-4 – Standard Sample Analyses Results for the 2017–2018 Batch with Standard AMIS0342 110
Figure 11-5 – Standard Sample Analyses Results for the 2017–2018 Batch with Standard AMIS0343 111
Figure 11-6 – Standard Sample Analyses Results for the 2017–2018 Batch with Standard AMIS0408 111
Figure 11-7 – Blank Sample Analyses from the 2017–2018 Campaign 112
Figure 11-8 – Scatterplot of Core Duplicates 113
Figure 11-9 – Correlation Between Original Samples and Pulp Duplicates 113
Figure 11-10: Check Assay Correlation Between Original Samples and Pulp Duplicates 115
Figure 11-11: Check Assay Distribution of the Difference Between Original Results and Pulp Duplicates 115
Figure 11-12: Standard Sample Analysis Results for the 2021 Batch with Standard AMIS0341 116
Figure 11-13: Standard Sample Analysis Results for the 2021 Batch with Standard AMIS0342 117
Figure 11-14: Standard Sample Analysis Results for the 2021 Batch with Standard AMIS0343 117
Figure 11-15: Standard Sample Analysis Results for the 2021 Batch with Standard AMIS0408 118

 

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Figure 11-16: Blank Sample Analyses from the 2021 Campaign 119
Figure 11-17: Correlation Between 2021 Original Samples and Coarse Duplicates 120
Figure 11-18: Correlation Between 2021 Original Samples and Pulp Duplicates 120
Figure 11-19: 2021 Check Assay Correlation Between SGS Originals and ALS Duplicates 121
Figure 11-20: Check Assay Distribution of the Difference Between SGS Originals and ALS Duplicates 122
Figure 12-1 – Witness Sample Original vs Control Sample Differences 126
Figure 12-2 – Witness Sample Original vs Control Sample Differences Frequency Distribution 127
Figure 12-3 – Witness Sample Original vs Control Sample Differences Correlation Analysis 127
Figure 13-1 – Overview of Typical Stage 1 Test work Flowsheet 129
Figure 13-2 – Sample Preparation Diagram for Stage 1 Variability Samples 130
Figure 13-3 – Effect of Combining Coarse DMS and -3.3 mm Middlings HLS Concentrates 135
Figure 13-4: Xuxa Main Pegmatite and Second Pegmatite Sampled in 2018 139
Figure 13-5: Petalite Distribution (%) in Xuxa Block Model (Plan View Looking North) 140
Figure 13-6: Spodumene Distribution (%) in Xuxa Block Model (Plan View Looking North) 140
Figure 13-7: Comparative Results for 5.5% and 6.0% Li2O Global Recovery for 9.5 mm Top Size 153
Figure 13-8: Relative Increase in Global Li2O Recovery for 9.5 mm Top Size 154
Figure 13-9: Comparative Results for 5.5% and 6.0% Li2O Global Yield for 9.5 mm Top Size 155
Figure 13-10: Relative Increase in Global Li2O Yield for 9.5 mm Top Size 156
Figure 13-11 – Lithium (Li2O) Grade and Localization of the Drill Holes used to produce the Barreiro Variability Samples 157
Figure 13-12 – BWi of the Composite Sample compared to the SGS Database 160
Figure 13-13 – Ai of Var 3 compared to the SGS Database 160
Figure 13-14 – Cumulative Lithium Grade - Stage Recovery Curves for HLS Tests 162
Figure 13-15 – Cumulative Lithium Grade – Global Recovery Curves for HLS Tests 162
Figure 14-1 – Xuxa Drill Hole Collar Locations 173
Figure 14-2 – Xuxa 1 m Composite Histogram 174
Figure 14-3 – Xuxa Pegmatite Solid (looking southeast) 176
Figure 14-4 – Xuxa Combined Correlogram 177
Figure 14-5 – Isometric View of Xuxa Search Ellipsoids 178
Figure 14-6 – Isometric View of the Xuxa Interpolated Block Model 178
Figure 14-7 – Statistical Comparison of Xuxa Assay, Composite and Block Data 179
Figure 14-8 – Comparison Xuxa Block Values Versus Composites Inside Blocks 179
Figure 14-9 – Xuxa Block Model Classification 180
Figure 14-10 – Barreiro Drillhole Collar Locations 183
Figure 14-11 – Barreiro 1 m Composite Histogram 185
Figure 14-12 – Sectional Interpretations of the Barreiro Pegmatite Unit (looking north and west) 186
Figure 14-13 – Barreiro Combined Correlogram 187
Figure 14-14 – Isometric View of Barreiro Search Ellipses 188
Figure 14-15 – Isometric View of the Barreiro Interpolated Block Model 188
Figure 14-16 – Statistical Comparison of Barreiro Assay, Composite and Block Data 189
Figure 14-17 – Barreiro Block Values Versus Composites Inside Those Blocks 189
Figure 14-18 – Barreiro Block Model Classification 191
Figure 14-19: Isometric View Looking Northeast: Barreiro Deposit Mineral Resource Block Grades and Revenue Factor 1 Pit 192
Figure 14-20 – Murial Drill Hole Collar Locations 194
Figure 14-21 – Murial 1 m Composite Histogram 195
Figure 14-22 – Murial Pegmatite Solid (looking west) 196
Figure 14-23 – Isometric View of Murial Search Ellipsoids 198
Figure 14-24 – Isometric View of Murial Interpolated Block Model 198
Figure 14-25 – Statistical Comparison of Murial Assay, Composite and Block Data 199
Figure 14-26 – Murial Block Values Versus Composites Inside Those Blocks 200

 

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Figure 14-27 – Murial Block Model Classification 203
Figure 14-28 – Lavra Do Meio Drill Hole Collar Locations 205
Figure 14-29 – Lavra do Meio 1 m Composite Histogram 206
Figure 14-30 – Lavra do Meio Pegmatite Solid (looking west) 207
Figure 14-31 – Lavra do Meio Combined Correlogram 208
Figure 14-32 – Isometric View of Lavra do Meio Search Ellipses 208
Figure 14-33 – Isometric View of Lavra Do Meio Interpolated Block Model 209
Figure 14-34 – Statistical Comparison of Lavro Do Meio Assay, Composite and Block Data 209
Figure 14-35 – Lavra Do Meio Block Values Versus Composites Inside Those Blocks 210
Figure 14-36 – Lavra Do Meio Block Model Classification 214
Figure 15-1: Final Xuxa Mine Configuration 216
Figure 15-2: Xuxa North and South Pit Geotechnical Sectors 218
Figure 15-3: Grade x Tonnage Curve with Selectivity Results Based on Local Uniform Conditioning Estimate 220
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%) 221
Figure 15-5: Schematic Representation of the Dilution Analysis 221
Figure 15-6: Xuxa Tonnage vs Partial Percentage – Dilution – 5 m 222
Figure 15-7: Tonnage vs Partial Percentage – Dilution – 1 m 224
Figure 15-8: Tonnage vs Partial Percentage – Solid Internal Dilution – 5 m 225
Figure 15-9: Pit by Pit Graph of Optimization Results 226
Figure 15-10: Xuxa Pit Wall Configuration 227
Figure 15-11: Xuxa Pit Ramp Design 230
Figure 15-12: Xuxa Final Optimized Pit Design 232
Figure 15-13: Final Barreiro Mine Configuration 234
Figure 15-14: Barreiro Pit Geotechnical Sectors 235
Figure 15-15: Barreiro Grade x Tonnage Curve with Selectivity Results Based on Local Uniform Conditioning Estimate 236
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%) 237
Figure 15-17: Schematic Representation of the Dilution Analysis 238
Figure 15-18: Barreiro Tonnage vs Partial Percentage Curves 240
Figure 15-19: Barreiro Nested Pit Tonnage and NPV 240
Figure 15-20: Barreiro Pit Wall Configuration 241
Figure 15-21: Barreiro Pit Ramp Design 243
Figure 15-22: Barreiro Final Operational Pit Design 244
Figure 16-1: Kinematic Analysis of Sector A, Xuxa North Pit 244
Figure 16-2: Xuxa North Pit, Sector A Stability Analysis, FS=1.47 245
Figure 16-3: Xuxa North Pit, Sector C Stability Analysis, FS=1.56 246
Figure 16-4: Xuxa North and South Pits with Geotechnical Sectors 247
Figure 16-5: Regional Hydrogeological Conceptual Model 248
Figure 16-6: Xuxa North and South Pits Separated by Piaui River 250
Figure 16-7: Potentiometric Map of the Xuxa Pit Region 252
Figure 16-8: Relationship between RQD and Depth Evaluated in the Block Model for the Proposed Pits 254
Figure 16-9: Steady-State Calibration Graph of Calculated vs Observed Head Values 257
Figure 16-10: Equipotential Surface of Groundwater Level in Year-9 Simulation Plan 258
Figure 16-11: Xuxa North and South Pits Year 1 258
Figure 16-12: Xuxa North and South Pits Year 2 259
Figure 16-13: Xuxa North and South Pits Year 3 260

 

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Figure 16-14: Xuxa North and South Pits Year 4 261
Figure 16-15: Xuxa North and South Pits Year 5 261
Figure 16-16: Xuxa North and South Pits Year 6 262
Figure 16-17: Xuxa North and South Pits Year 7 266
Figure 16-18: Xuxa North and South Pits Year 8 267
Figure 16-19: Explosives Magazines in Container 270
Figure 16-20: Example of Ammonium Nitrate Emulsion Storage Structure 271
Figure 16-21: Schematic of Wash Ramp Oil-Water Separator 282
Figure 16-22: Schematic of Solid Waste Temporary Storage Facility 284
Figure 16-23: Image Analysis and Calculation of Granulometric Distribution 285
Figure 16-24: OPTV-derived stereogram showing two main joint structures at Barreiro 286
Figure 16-25: Barreiro Pit Sectorization 287
Figure 16-26: Barreiro kinematic analysis for sector 1 with 5% planar rupture occurring 287
Figure 16-27: Barreiro kinematic analysis for sector 1 with 4% planar rupture occurring 288
Figure 16-28: Barreiro kinematic analysis for sector 3 with 4% planar rupture occurring 288
Figure 16-29: Barreiro kinematic analysis for sector 4 with 4% planar rupture occurring 289
Figure 16-30: Barreiro kinematic analysis for sector 5 with 5% planar rupture occurring 289
Figure 16-31: Barreiro Kinematic analysis for sector 5 with 30% planar rupture occurring 290
Figure 16-32: Analysis of section 01 with FS = 1.92 290
Figure 16-33: Analysis of section 02 with FS = 1.43 291
Figure 16-34: Analysis of section 03 with FS = 1.80 291
Figure 16-35: Analysis of section 04 with FS = 1.99 292
Figure 16-36: Analysis of section 05 with FS = 2.18 294
Figure 16-37: Jequitinhonha River Basin in Minas Gerais state, Brazil 295
Figure 16-38: Route map and drainage points inspected in the Barreiro area 296
Figure 16-39: Drill hole locations and potentiometric map of the Barreiro area 298
Figure 16-40: Barreiro geotechnical drill hole locations 301
Figure 16-41: Barreiro Pit Year 1 301
Figure 16-42: Barreiro Pit Year 2 302
Figure 16-43: Barreiro Pit Year 3 302
Figure 16-44: Barreiro Pit Year 4 303
Figure 16-45: Barreiro Pit Year 5 303
Figure 16-46: Barreiro Pit Year 6 304
Figure 16-47: Barreiro Pit Year 10 304
Figure 16-48: Barreiro Pit Year 12 309
Figure 16-49: Explosives Magazines in Container 310
Figure 16-50: Example of Ammonium Nitrate Emulsion Storage Structure 310
Figure 16-51: Schematic of Wash Ramp Oil-Water Separator 314
Figure 16-52: Schematic of Solid Waste Temporary Storage Facility 315
Figure 16-53: Image Analysis and Calculation of Granulometric Distribution 323
Figure 17-1: Xuxa Process Plant 326
Figure 17-2: Block Flow Diagram for Xuxa Crushing Circuit and DMS Plant 327
Figure 17-3: Sigma Crushing and DMS Plant Overview 328
Figure 17-4: Sigma Primary Crushing Facility and Crushed Ore Bin 329
Figure 17-5: Sigma Xuxa DMS Plant and Product Stockpiles 330
Figure 17-6: Xuxa and Barreiro Process Plant Layout (2021 Design) 334
Figure 17-7: Block Flow Diagram for the Barreiro Crushing Circuit and DMS Plant 336
Figure 18-1– Sigma Lithium Project General Layout Plan for Xuxa 341
Figure 18-2– Overall Site Plan 342
Figure 18-3: Schematic of the proposed municipal road upgrades 343
Figure 18-4: Proposed municipal access road and community bypass road 343

 

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Figure 18-5 – Proposed Bridge Location Xuxa Mine 344
Figure 18-6 – Xuxa Mine Water Balance 346
Figure 18-7 – Intake Water / Water Treatment 348
Figure 18-8: Conceptual Representation of Workshop Areas 351
Figure 18-9: Xuxa Waste Piles Location Map 353
Figure 18-10: Xuxa Waste Piles Geotechnical Sampling Locations 354
Figure 18-11: Constructive Sequencing of the 340 M Level of the Waste Pile Berm 355
Figure 18-12: Stability Analysis Section AA for Xuxa Waste Pile 03 357
Figure 18-13: Proposed Location of Barreiro Waste Dump 358
Figure 18-14: Final Mine Configuration Showing Xuxa and Barreiro Pits and Sigma Processing Plant 360
Figure 18-15 – Product Transport Routing from Xuxa to Ilhéus 365
Figure 19-1: Lithium Supply-Demand Forecast 366
Figure 19-2: Lithium Demand Breakdown by End-Use 2022 367
Figure 19-3: Electric Vehicle Sales as a Share of Total Cars 367
Figure 19-4: Lithium Feedstock Supply Forecast 368
Figure 19-5 Lithium Chemical Supply Breakdown 369
Figure 19-6: Long-Term Supply C1 Lithium Carbonate Cost Curve 370
Figure 19-7: Battery-Grade Lithium Chemical Price Forecast 370
Figure 19-8: Spodumene Price Forecast 380
Figure 20-1 – Location of Areas of Interest and Properties 384
Figure 20-2: Sigma Wildlife Rehabilitation Centre and Seedling Nursery 390
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. 390
Figure 20-4: Herpetofauna: A) Neotropical Ameiva, B) Tropidurus oreadicus, C) Leptodactilus fuscus; D) Tegu; E) Rhinella granulosa and F) Rhinellaschneideri. 390
Figure 20-5: Terrestrial mammalian fauna: A) wild dog; B) skunk; C) big-eared opossums; and D) footprint of Procyon cancrivorus. 391
Figure 20-6 – Project Status Plan with Mining Applications 392
Figure 22-1: Spodumene Concentrate Price Forecast 421
Figure 22-2: Phase 1 After-Tax Cash Flow and Cumulative Cash Flow Profile @ 6.0% SC 425
Figure 22-3: Phase 1 After-Tax Cash Flow and Cumulative Cash Flow Profile @ 5.5% SC 425
Figure 22-4: Phase 1 After-Tax Cash Flow and Cumulative Cash Flow Profile @ 5.2% SC 425
Figure 22-5 : Phase 1 Financial Model Summary @ 6.0% SC 426
Figure 22-6: Phase 1 Financial Model Summary @ 5.5% SC 427
Figure 22-7: Phase 1 Financial Model Summary @ 5.2% SC 428
Figure 22-8: Phase 1 6.0% SC After-Tax NPV Sensitivity Analysis (US$ B) 429
Figure 22-9: Phase 1 5.5% SC After-Tax NPV Sensitivity Analysis (US$ B) 429
Figure 22-10: Phase 1 5.2% SC After-Tax NPV Sensitivity Analysis (US$ B) 430
Figure 22-11: Phase 1 6.0% SC After-Tax IRR Sensitivity Analysis (%) 430
Figure 22-12: Phase 1 5.5% SC After-Tax IRR Sensitivity Analysis (%) 430
Figure 22-13: Phase 1 5.2% SC After-Tax IRR Sensitivity Analysis (%) 431
Figure 22-14: Phase 2 After-Tax Cash Flow and Cumulative Cash Flow Profile @ 6.0% SC 434
Figure 22-15: Phase 2 After-Tax Cash Flow and Cumulative Cash Flow Profile @ 5.5% SC 434
Figure 22-16: Phase 2 After-Tax Cash Flow and Cumulative Cash Flow Profile @ 5.2% SC 434
Figure 22-17: Phase 2 Financial Model Summary @ 6.0% SC 435
Figure 22-18: Phase 2 Financial Model Summary @ 5.5% SC 436
Figure 22-19: Phase 2 Financial Model Summary @ 5.2% SC 437
Figure 22-20: Phase 2 6.0% SC After-Tax NPV Sensitivity Analysis (US$ B) 438
Figure 22-21: Phase 2 5.5% SC After-Tax NPV Sensitivity Analysis (US$ B) 438
Figure 22-22: Phase 2 5.2% SC After-Tax NPV Sensitivity Analysis (US$ B) 439

 

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Figure 22-23: Phase 2 6.0% SC After-Tax IRR Sensitivity Analysis (%) 439
Figure 22-24: Phase 2 5.5% SC After-Tax IRR Sensitivity Analysis (%) 439
Figure 22-25: Phase 2 5.2% SC After-Tax IRR Sensitivity Analysis (%) 440
Figure 22-26: Phase 1+2 After-Tax Cash Flow and Cumulative Cash Flow Profile @ 6.0% SC 443
Figure 22-27: Phase 1+2 After-Tax Cash Flow and Cumulative Cash Flow Profile @ 5.5% SC 443
Figure 22-28: Phase 1+2 After-Tax Cash Flow and Cumulative Cash Flow Profile @ 5.2% SC 444
Figure 22-29: Phase 1+2 Financial Model Summary @ 6.0% SC 445
Figure 22-30: Phase 1+2 Financial Model Summary @ 5.5% SC 446
Figure 22-31: Phase 1+2 Financial Model Summary @ 5.2% SC 447
Figure 22-32: Phase 1+2 6.0% SC After-Tax NPV Sensitivity Analysis (US$ B) 447
Figure 22-33: Phase 1+2 5.5% SC After-Tax NPV Sensitivity Analysis (US$ B) 448
Figure 22-34: Phase 1+2 5.2% SC After-Tax NPV Sensitivity Analysis (US$ B) 448
Figure 22-35: Phase 1+2 6.0% SC After-Tax IRR Sensitivity Analysis (%) 448
Figure 22-36: Phase 1+2 5.5% SC After-Tax IRR Sensitivity Analysis (%) 449
Figure 22-37: Phase 1+2 5.2% SC After-Tax IRR Sensitivity Analysis (%) 451
Figure 24-1: Xuxa Schedule 451

 

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CERTIFICATE OF AUTHOR

HOMERO DELBONI JR

 

I, Homero Delboni Jr, B.E., M.Eng.Sc., Ph.D., 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, Phase 1 DFS and Phase 2 PFS Update of the NI 43-101 Technical Report.” with an effective date of 24th February 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 Masters 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 18.4.2, 18.4.4.2, 18.8 and 18.8.8.1.2, 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 25th May 2022 at São Paulo, SP - Brazil.

 

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

 

_________________________________________________________

Homero Delboni Jr, B.E., M.Eng.Sc., Ph.D., MAusIMM – CP (Metallurgy)
Senior Consultant, Promon Engenharia, MAusIMM #112813

 

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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, Phase 1 DFS and Phase 2 PFS Update of the NI 43-101 Technical Report.” with an effective date of 24th February 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 25th May 2022 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, Phase 1 DFS and Phase 2 PFS Update of the NI 43-101 Technical Report” with an effective date of 24th February 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 25th May 2022 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, P.Eng., 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, Phase 1 DFS and Phase 2 PFS Update of the NI 43-101 Technical Report” with an effective date of 24th February 2022 (Technical Report).

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 April 17-18, 2019.

7.I have read NI 43-101 and have participated in the preparation of this Technical Report and am responsible for Sections 15, 16, 18.4.2, 18.4.4.2, 18.8, 18.8.1.2, 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 25th May 2022, 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
BRIAN TALBOT

 

I, Brian Talbot, FAusIMM, do hereby certify:

 

1.I am a Consulting Process Engineer for Rtek Pty LTD. with a business address at 33 Richardson St West Perth.

2.This certificate applies to the Technical Report entitled “Grota do Cirilo Lithium Project, Aracuai and Itinga Regions, Minas Gerais, Brazil, Phase 1 DFS and Phase 2 PFS Update of the NI 43-101 Technical Report” with an effective date of 24th February 2022 (Technical Report).

3.I am a graduate of the University of the Witwatersrand (BSc Engineer Chemical) and I am a member in good standing of AusIMM (#3001296). I have worked as a chemical engineer since 1994.

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 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 25th May 2022, at Perth, Western Australia.

 

 

“Signed and sealed” Brian Talbot, FAusIMM

 

 

   
Brian Talbot, 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 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 NI 43-101 Technical Report (the Report) on Sigma’s Grota do Cirilo project located in Minas Gerais State, Brazil.

 

This report includes a Definitive Feasibility Study (DFS) on the phase 1 Xuxa project and a Pre-feasibility Study (PFS)) on the phase 2 Barreiro 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 April 11, 2022.

 

Mineral Resources are reported for four pegmatite bodies, Xuxa, Barreiro, Murial and Lavra do Meio. Mineral Reserves are reported for the Xuxa and Barreiro deposits.

 

A PFS, which is the subject of this Report, has been conducted on the Barreiro deposit.

 

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/h 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.

 

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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.

 

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.

 

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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.

 

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.

 

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 357 core holes totalling 60,820 m. To date, this drilling has concentrated on the Grota do Cirilo pegmatites. Drilling was at 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 in 2017 and 2018.

 

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 and 2021 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 the Xuxa DFS and the Barreiro PFS.

 

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 course of the 2012–2021 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 2020-2021 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 2020-2021 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 2020-2021 sampling programs. The 2017–2018 campaign used seven certified standards from African Mineral Standards (AMIS), an international supplier of certified reference materials while the 2020-2021 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. Results were considered acceptable, and no material accuracy issues were noted.

 

During the 2017–2018 and 2020-2021 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 721 analytical blanks were analysed during the 2014, 2017–2018 and 2020-2021 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 and Lavra do Meio deposits.

 

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.

 

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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.

 

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 and from October 18 to 21, 2021. 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.

 

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.

 

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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

 

Drill core samples from the Xuxa pegmatite deposit were processed at the SGS Lakefield facility in 2018 and 2022, while samples from Barreiro were tested between November 2020 and May 2021. 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.

 

1.10.1Xuxa

 

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.

 

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%.

 

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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%.

 

1.11Mineral 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 models used a 6 m x 3 m x 5 m block size. Murial and Lavra do Meio 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.

 

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

 

The grade interpolation for the Xuxa, Barreiro and Lavra do Meio 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.

 

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.

 

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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.

 

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

 

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 1-4 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, and the Barreiro estimate has an effective date of February 10, 2022. The QP for the estimates is Mr. Marc-Antoine Laporte, P.Geo., an SGS employee.

 

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Table 1-1 – 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 1.1 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 1-2 – 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 1-2 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.

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.

 

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Table 1-3 – 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 1.3 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 1-4Lavra 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 1.4 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.

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.

 

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1.12Mineral Reserve Estimates

 

Xuxa Mineral Reserve estimates have an effective date of 26 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 1-5.

 

Table 1-5 – 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

 

The total Proven and Probable Mineral Reserves are as presented in Table 1-6.

 

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Table 1-6 – 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.

 

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 1-7.

 

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Table 1-7: 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

 

The total Proven and Probable Mineral Reserves are as presented in Table 1-8.

 

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Table 1-8: 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.

 

1.13Mining Methods

 

Sigma has undertaken a program of resource drilling for the Xuxa and Barreiro deposits. Most of these 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

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 and this fleet will be 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

 

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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:

 

Pre-stripping the pit to liberate mineralized material

Pit cut-backs in years 4 to 6 to expand and deepen 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 and this fleet will be 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).

 

1.14.1Processing Plant Description

 

The Xuxa plant throughput capacity is based on 1.5 Mtpa (dry) of ore fed to the crushing circuit, while the Barreiro plant is based on a nominal 1.85 Mt throughput capacity.

 

Both 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.

 

Font-End Engineering Design (FEED) is currently underway 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 Barreiro concentrator is based on pre-feasibility-level test work conducted at 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 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 will be 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 Barreiro project will utilise the infrastructure developed for the Xuxa project.

 

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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 1-9 shows the capacities of the Xuxa waste piles.

 

Table 1-9 – 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 – 20 m bench height, 38° face angle, 12 m access ramp and a maximum gradient of 10%.

 

Table 1-10 show the capacity of the Barreiro waste pile.

 

Table 1-10: Barreiro Waste Pile Storage

 

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

 

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 waste pile for disposal.

 

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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).

 

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.

 

1.16.1Demand and Consumption

 

Lithium’s demand growth profile increased dramatically in 2021, driven by structural changes in the automotive industry with manufactures increasingly transitioning towards electric vehicles (EVs). Benchmark Mineral Intelligence estimates global EV penetration reached 7.9% in 2021, up from 4.0% in 2020, as global EV sales continue to accelerate, particularly from Europe and China.

 

Benchmark Mineral Intelligence estimates that 2021 lithium supply-demand ended in a deficit position and expects that it will tighten further going forward, with 2022 forecasted to have a base case demand from battery end-use of 541 kt LCE, a 32% increase from 2021. This deficit position is expected to continue to increase, reaching a net deficit position of 156 kt LCE by 2030 and 2.1 Mt LCE by 2040.

 

Benchmark Mineral Intelligence's robust demand outlook is partially driven by continued EV adoption, with global EV penetration expected to climb to 21% of total sales by 2025 and reach 73% by 2040.

 

1.16.2Supply

 

Benchmark Mineral Intelligence expects lithium supply to increase over the 604 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 2.2 Mt LCE by 2030 and 3.7 Mt LCE by 2040. Benchmark Mineral Intelligence’s supply forecast includes expansions from existing mines as well as new entrants developing pre-production projects.

 

1.16.3Contracts

 

On April 5, 2019, Sigma entered into a binding head of agreement (the Agreement) for a strategic offtake and funding partnership with Mitsui & Co., Ltd. of Japan (Mitsui) for a portion of the funding required for the capital expenditures and project construction.

 

Pursuant to the Agreement, Mitsui and Sigma had agreed terms on:

 

Production pre-payment to Sigma of US$30,000,000 for battery-grade lithium concentrate supply of up to 55,000 t annually over six years, extendable for five years plus an off-take agreement supplementary 25,000 t of product annually
Advancement of deposit for long-lead items for the project
Strategic collaboration to leverage Mitsui’s considerable global logistics and battery materials marketing expertise as well as an agreement to continue discussions regarding additional funding for further exploration and development of Sigma’s mineral properties
Mitsui’s right to participate in Sigma’s future capital for production expansion with other deposits conditional to concluding a feasibility study and Mineral Reserves estimates

 

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Sales prices are set quarterly based on the published price of nominal arms-length chemical-spodumene concentrate above 6% Li2O (SC6).

 

An initial deposit payment of US$3.0 million was received by Sigma on April 4, 2019, but any further rights of the parties to the Agreement were subject to certain conditions not met, including the negotiation and execution of related definitive offtake agreements with Mitsui. It remains to be determined whether a mutually acceptable role for Mitsui can be agreed upon.

 

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.

 

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.

 

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.

 

1.16.4Price 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$33,900/t and US$2,900/t in 2023, respectively. Benchmark Mineral Intelligence then expects prices to stabilize at higher levels in 2024 and begin to decline to more stable levels in a balanced supply-demand market starting in 2025. Benchmark Mineral Intelligence estimates longer term real lithium hydroxide and spodumene 6% prices of US$16,300/t and US$850/t in 2030, respectively.

 

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.

 

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.

 

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.

 

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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

 

A Concurrent Environmental Licensing Type CEL 2 (LP + LI) will be required in support of operations.

 

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

 

The CEL 2 (LP + LI) 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 submitted for approval in March 2020 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.

 

The formalization of the environmental licensing process also included requesting and granting of the EIA. This allows Sigma environmental intervention in an approximately 64 ha area.

 

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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.

 

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.

 

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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 Environmental Impact Study - EIA and its respective Environmental Impact Report - RIMA will be submitted to the regulatory agency, Bureau of Priority Projects - SUPPRI, as a supporting document to obtain a Preliminary License - LP and an Installation License - LI for Grota do Cirilo Project - Barreiro Pegmatite.

 

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

 

The environmental licensing process started in October 2020 and will be formalized with the submission of the technical studies requested through the Environmental Licensing System - SLA, request No.: 2020.10.01.003.0003780 for the production of: 1,500,000 t/year for open pit mining and 251.89 ha for waste heaps.

 

1.18Capital and Operating Costs

 

1.18.1Capital Cost Estimate

 

As a basis for the CAPEX build-up, engineering and design were advanced to a FEED level for the Xuxa plant and a pre-feasibility level for the Barreiro plant with approval of key deliverables obtained from Sigma. These included the design basis, process design criteria, block flow diagram, process flow diagram, a high-level mass balance basis of design along with a similar project execution plan, schedule and site conditions as Xuxa Phase 1 FEED.

 

The total CAPEX for Xuxa including the Estimated Vat Tax Incentive is US$131.6 M. The total CAPEX already disbursed during construction is US$20,700,000 with US$110,900,545 of CAPEX remining.

 

The total CAPEX for Barreiro including the Estimated Vat Tax Incentive is US$75.7 M.

 

The CAPEX estimate has an accuracy of ±25% and is summarized in Table 1-11 (Xuxa) and Table 1-12 (Barreiro).

 

Table 1-11 – Capital Cost Estimate Summary Xuxa

 

AREA TOTALS
   
 

DIRECTS + INDIRECTS

(USD)

CONTINGENCY

(USD)

TOTAL

(USD)

001 Mine  7,856,938    604,984    8,461,922  
002 Plant  64,841,255    4,992,777    69,834,032  
003 Environmental  15,387,006    1,184,799    16,571,805  
004 EPCM & Engineering Services  17,867,543    1,375,801    19,243,344  
005 Substation and Utility Power Supply  6,888,863    530,442    7,419,305  
Total Construction Capital Cost  112,841,604    8,688,804    121,530,408  
006 Owner’s Project Costs  8,901,677    890,168    9,791,844  
007 Working Capital and Spares  6,137,293    –    6,137,293  
Total Construction Capital Cost (ex VAT Tax Incentive)  127,880,574    9,578,971    137,459,545  
009 Estimated VAT Tax Incentive (5,859,000)  –   (5,859,000)
Total Construction Capital Cost  122,021,574    9,578,971    131,600,545  
       
008 Sustaining and Deferred Capital 3,200,000 246,400  3,446,400  

 

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Table 1-12: Capital Cost Estimate Summary Barreiro

 

AREA

TOTALS

(USD)

 

DIRECTS + INDIRECTS

(USD)

CONTINGENCY

(USD)

TOTAL

(USD)

001 Mine  2,096,208    161,408    2,257,616  
002 Plant  50,056,062    3,854,317    53,910,379  
003 Environmental  6,747,201    519,534    7,266,735  
004 EPCM & Engineering Services  10,726,444    825,936    11,552,380  
005 Substation and Utility Power Supply  –    –    –  
006 Owner’s Project Costs  3,000,000    231,000    3,231,000  
007 Working Capital and Spares  937,293    72,172    1,009,465  
Total Construction Capital Cost (VAT Tax Incentive)  73,563,208    5,664,367    79,227,575  
008 Estimated VAT Tax Incentive (3,500,000)  –   (3,500,000)
Total Construction Capital Cost (VAT Tax Incentive)  70,063,208    5,664,367    75,727,575  
       
008 Sustaining and Deferred Capital  7,070,000    544,390    7,614,390  

 

Note: The Barreiro 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 OPEX for the Xuxa concentrator will be US$10.2/t of ore feed (or US$55.73/t of spodumene concentrate produced). The estimated OPEX for the Barreiro concentrator is US$8.4/t of ore feed (or US$66.3/t of spodumene concentrate produced).

 

Is it worth noting that General and Administration (G&A) costs to manage the site (including the two concentrators) has been accounted for into the Xuxa concentrator OPEX exercise, which explains the majority of the cost difference between to two processing plants.

 

Operating cost estimates are summarized in Table 1-13 (Xuxa) and Table 1-14 (Barreiro)

 

Table 1-13: Xuxa Operating Cost Estimate Summary

 

DESCRIPTION OPEX (US$)
Mining (US$/t material mined) $2.06
Process (US$/t ore feed) $10.2
G&A (US$/t ore feed) $3.3
Shipping (US$/t SC) $119

 

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Table 1-14: Barreiro Operating Cost Estimate Summary

 

DESCRIPTION OPEX (US$)
Mining (US$/t material mined) $2.68
Process (US$/t ore feed) $8.4
G&A (US$/t ore feed) $4.3
Shipping (US$/t SC) $110

 

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 deposit (Phase 2); and
both Phase 1 and Phase 2 (Phase 1+2).

 

Additionally, the economic analyses contemplate the production of spodumene concentrate (SC) at grades of 6.0%, 5.5% and 5.2% Li2O, in order to consider the current lithium market conditions.

 

The base case scenario after-tax net present value (NPV) results are detailed in Table 1-15 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 PFS estimates for Phase 1 and Phase 2, respectively. In contrast, the Project’s economic returns remain most sensitive to changes in spodumene prices, feedstock grades and recovery rates.

 

Table 1-15 – Base Case After-Tax NPVs

 

Modelled Case Unit @ 6.0% SC @ 5.5% SC @ 5.2% SC
Phase 1 US$ M $2,187 $2,643 $2,820
Phase 2 US$ M $1,853 $2,438 $2,611
Phase 1+2 US$ M $4,043 $5,083 $5,435

 

Phase 1, Phase 2 and Phase 1+2 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 and Phase 1+2, the Sudene tax incentive is expected to be renewed after the 10th anniversary of achieving at least 20% of their production capacities.

 

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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 and Phase 1+2 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 up to 286 ktpa of lithium concentrate, delivering US$485 million of annual free cash flow, at a 5.2% SC grade.

 

The base case scenario results are detailed in Table 1-16 below.

 

Table 1-16: Phase 1 Base Case Scenario Results

 

Item Unit @ 6.0% SC @ 5.5% SC @ 5.2% SC
After-Tax NPV @ 8% US$ M $2,187 $2,643 $2,820
After-Tax IRR % 482% 571% 606%
After-Tax Payback Period years 0.3 0.2 0.2

 

The key technical assumptions used in the base case are highlighted below in Table 1-17.

 

Table 1-17: Key Phase 1 Technical Assumptions

 

Item Unit @ 6.0% SC @ 5.5% SC @ 5.2% SC
Total Ore Processed (ROM) Mt 11.8 11.8 11.8
Annual ROM Ore Processed Mt 1.5 1.5 1.5
Run-Rate SC Production ktpa 230 270 286
Run-Rate LCE Production (Note 1) ktpa 34 37 37
Strip Ratio ratio 16.4: 1 16.4: 1 16.4: 1
Average Li2O Grade % 1.55% 1.55% 1.55%
Spodumene Recovery Rate % 60.4% 65.0% 65.0%
Spodumene Concentrate Grade % Li2O 6.0% 5.5% 5.2%
Operating Life years 8 8 8
Total Cash Cost (FOB) US$/t SC $386 $339 $324
Transportation Costs (CIF China) US$/t SC $119 $119 $119
Total Cash Cost (CIF China) US$/t SC $505 $458 $443
AISC (CIF China) US$/t SC $506 $459 $444
Mining Costs US$/t Material Mined $2.06 $2.06 $2.06
Processing Costs US$/t ROM $10.20 $10.20 $10.20
G&A Costs US$/t ROM $3.26 $3.26 $3.26

 

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 for Phase 1 is estimated up to US$5.7 billion, an average revenue of US$2,499/t 5.2% SC with total operating costs (including royalty payments and commercial discounts) of US$1.0 billion at an average cost of US$443/t 5.2% SC. The resulting after-tax earnings margin (gross revenue less realization, operating costs and taxes) was estimated at US$3.9 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 PFS Economic Analysis

 

The Phase 2 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. Phase 2 is expected to generate run-rate production of up to 276 ktpa of lithium concentrate, delivering US$366 million of annual free cash flow, at a 5.2% SC grade.

 

The base case scenario results are detailed in Table 1-18 below.

 

Table 1-18: Phase 2 Base Case Scenario Results

 

Item Unit @ 6.0% SC @ 5.5% SC @ 5.2% SC
After-Tax NPV @ 8% US$ M $1,853 $2,438 $2,611
After-Tax IRR % 601% 764% 813%
After-Tax Payback Period years 0.2 0.2 0.1

 

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The key technical assumptions used in the base case are highlighted below in Table 1-19.

 

Table 1-19: Key Phase 2 Technical Assumptions

 

Item Unit @ 6.0% SC @ 5.5% SC @ 5.2% SC
Total Ore Processed (ROM) Mt 21.8 21.8 21.8
Annual ROM Ore Processed Mt 1.8 1.8 1.8
Run-Rate SC Production ktpa 210 261 276
Run-Rate LCE Production (Note 1) ktpa 31 36 36
Strip Ratio ratio 12.5: 1 12.5: 1 12.5: 1
Average Li2O Grade % 1.37% 1.37% 1.37%
Spodumene Recovery Rate % 50.9% 57.9% 57.9%
Spodumene Concentrate Grade % Li2O 6.0% 5.5% 5.2%
Operating Life years 12 12 12
Total Cash Cost (FOB) US$/t SC $408 $340 $325
Transportation Costs (CIF China) US$/t SC $110 $110 $110
Total Cash Cost (CIF China) US$/t SC $519 $451 $435
AISC (CIF China) US$/t SC $521 $453 $437
Mining Costs US$/t Material Mined $2.68 $2.68 $2.68
Processing Costs US$/t ROM $8.40 $8.40 $8.40
G&A Costs US$/t ROM $4.30 $4.30 $4.30

 

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

 

The total gross revenue derived from the sale of spodumene concentrate for Phase 2 is estimated up to US$6.9 billion, an average revenue of US$2,074/t 5.2% SC with total operating costs (including royalty payments and commercial discounts) of US$1.4 billion at an average cost of US$435/t 5.2% SC. The resulting after-tax earnings margin (gross revenue less realization, operating costs and taxes) was estimated at US$4.4 billion.

 

A sensitivity analysis for Phase 2 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 2 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 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.

 

1.19.4Phase 1 + Phase 2 PFS Economic Analysis

 

The Phase 1+2 economic analysis is based on a thirteen-year operation sourcing feedstock ore from the Xuxa and Barreiro’s combined Mineral Reserves of 33.6 Mt. Phase 1+2 is expected to generate run-rate production of up to 562 ktpa of lithium concentrate, delivering US$637 million of annual free cash flow, at a 5.2% SC grade.

 

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

 

Table 1-20: Phase 1+2 Base Case Scenario Results

 

Item Unit @ 6.0% SC @ 5.5% SC @ 5.2% SC
After-Tax NPV @ 8% US$ M $4,043 $5,083 $5,435
After-Tax IRR % 495% 589% 624%
After-Tax Payback Period years 0.3 0.3 0.2

 

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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+2 Technical Assumptions

 

Item Unit @ 6.0% SC @ 5.5% SC @ 5.2% SC
Total Ore Processed (ROM) Mt 33.6 33.6 33.6
Annual ROM Ore Processed Mt 2.6 2.6 2.6
Run-Rate SC Production ktpa 440 531 562
Run-Rate LCE Production (Note 1) ktpa 65 72 72
Strip Ratio ratio 13.8: 1 13.8: 1 13.8: 1
Average Li2O Grade % 1.43% 1.43% 1.43%
Spodumene Recovery Rate % 54.4% 60.5% 60.5%
Spodumene Concentrate Grade % Li2O 6.0% 5.5% 5.2%
Operating Life years 13 13 13
Total Cash Cost (FOB) US$/t SC $399 $340 $325
Transportation Costs (CIF China) US$/t SC $114 $114 $114
Total Cash Cost (CIF China) US$/t SC $513 $454 $438
AISC (CIF China) US$/t SC $515 $455 $440
Mining Costs US$/t Material Mined $2.39 $2.39 $2.39
Processing Costs US$/t ROM $9.04 $9.04 $9.04
G&A Costs US$/t ROM $3.93 $3.93 $3.93

 

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

 

The total gross revenue derived from the sale of spodumene concentrate from Phase 1+2 is estimated up to US$12.6 billion, an average revenue of US$2,247/t 5.2% SC with total operating costs (including royalty payments and commercial discounts) of US$2.5 billion at an average cost of US$438/t 5.2% SC. The resulting after-tax earnings margin (gross revenue less realization, operating costs and taxes) was estimated at US$8.3 billion.

 

A sensitivity analysis for Phase 1+2 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 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 after-tax NPV is more sensitive to variation in spodumene price, lithium grade, and spodumene recovery rates.

 

Phase 1+2 after-tax IRR is not significantly vulnerable to changes in Opex. In contrast, Phase 1+2 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 after-tax IRR is independent of the discount rate considered.

 

1.20Interpretation and Conclusions

 

Mineral Resources are reported for four pegmatite bodies, Xuxa, Barreiro, Murial and Lavra do Meio. Mineral Reserves are reported for the Xuxa and Barreiro deposits.

 

This report comprises a technical study assessing the proposed mining operations which contribute towards the findings of the DFS completed for Phase 1 and the PFS for Phase 2 of the Grota do Cirilo Project.

 

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The DFS outlines the requirements and parameters for the development of two open pits, namely North pit and the South pit. Phase 1 will mine 1.5 Mta ROM for 8 years. The Dense Media concentration plant is designed to produce 230 ktpa of 6% Li2O spodumene concentrate or 246 ktpa of 5.6% Li2O spodumene concentrate. The DFS describes all the related plant and mine direct and indirect infrastructure required for the project. The PFS outlines the requirements and parameters for the development of an open pit mine consisting of one pit on the Barreiro deposit (Phase 2), together with the concentration plant and related infrastructure to process 1.80 Mtpa of mineralized material per year for a LOM of 12.7 years.

 

The Company has made a construction decision for Phase 1 and has finalized a PFS for Phase 2 of the Grota do Cirilo Project. All statements regarding mine development or production in respect of both Phase 1 and 2 in this report are expressly qualified by this statement.

 

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
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
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 Xuxa DFS and Barreiro PFS. A phased work program is planned, which consists of continued exploration over the known pegmatites in the Grota do Cirilo area, together with the implementation of the recommendations of Xuxa DFS and the Barreiro project PFS recommendations.

 

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It is important to note that the recommendations for the different projects can be conducted concurrently.

 

1.21.1Geology and Resources

 

The QPs recommend that additional exploration drilling be conducted across the property to update existing resources and potentially discover new resources. The overall cost for the drill program is estimated at US$6.1M and consists of a 36,000 m drill program to test Xuxa, Barreiro, Nezinho do Chicao and Murial.

 

1.21.2Xuxa Recommendations

 

The recommendations for Xuxa will be implemented in the project execution phase, prior to commencement of operations, and are estimated to be a total of US$1,275,000, consisting of:

 

Process plant (testing for wet magnetic separation equipment, a middlings recrushing recovery trade-off study): US$60,000
Mine design (finalize topographic survey; complete density, moisture and blasted swell effect analyses for ore and waste; implement a reconciliation system and grade control program; evaluate underground mining potential for below the open pit levels of the mine, conduct a reserve study for underground mining; implement geotechnical monitoring system): US$345,000

 

1.21.3Barreiro Project Recommendations

 

Based on the results of the Barreiro PFS, the QPs recommend that the Company proceed to completing a definitive feasibility study (DFS) in respect of the Barreiro deposit.

 

The engineering recommendations for Barreiro should be implemented in the project execution phase, prior to commencement of operations, and consist of:

 

Complete studies relating to mine and waste heap geotechnics and hydrogeology considering geotechnical borehole complementation, borehole geotechnical relogging and televiewer program.
Develop an executive project for the Barreiro Waste pile.
Develop an executive project for a Barreiro ROM PAD including a crushing and screening station and a fines deposit in waste deposit or separately.
Review the mining project by updating the geotechnical parameters and considering a stockpile option to optimize the grade fed in beneficiation plant.

 

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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 NI 43-101 Technical Report (the Report) for the Sigma’s Grota do Cirilo Project located in Minas Gerais State, Brazil. (Figure 2 1). This includes a Definitive Feasibility Study (DFS) for the phase 1 Xuxa deposit and a Pre-feasibility Study (PFS) for the phase 2 Barreiro deposit.

 

 

 

Figure 2-1 – Project Location

 

2.1Terms of Reference

 

Mineral Resources are reported for four pegmatite bodies, 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 Mineral Reserves is February 24, 2022.

 

The overall effective date of the Report is the date of the financial analysis supporting the Mineral Reserves and is February 24, 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, Senior Consultant, Promon Engenharia
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. Brian Talbot, FAusIMM,

 

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, and October 18-21, 2021. 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.

 

Mr. Porfirio Cabaleiro Rodriguez visited the site from April 17-18, 2019. During this visit, he familiarized himself with general aspects of the proposed mine area, 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.

 

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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, Q1-2022: Lithium Forecast, Q1-2022.

 

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 through the following documents:

 

Sigma’s announcement on April 10, 2019, of the Sigma and Mitsui Binding Heads of Agreement. (Heads of Agreement - Lithium concentrate offtake dated March 25, 2019)
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.

 

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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.

 

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 disclaims 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