Bankan Gold Project Siguiri Basin, Guinea Technical Report
Effective Date: 31 July 2025
Authors
Philip Jankowski, MSc, FAusIMM Ross Cheyne, BEng (Mining), FAusIMM Julian Broomfield, BEng (Mining), FAusIMM
Peter O'Bryan, BEng (Mining), MEngSc (RockEng),
MAusIMM(CP)
Pieter Labuschagne, MSc (Hydrogeology), MIAH,
Pr.Sci.Nat 400386/11 Stewart Watkins, BEng (Chem), FAusIMM
Predictive Discovery Limited
ABN 11 127 171 877
Suite 8, 110 Hay Street, Subiaco WA 6008
T +61 8 9216 1020
https://www.predictivediscovery.com
CONTENTSIntroduction, Location and Ownership 25
History 26
Geological Setting and Mineralisation 27
Exploration 28
Drilling 29
Sample Preparation, Analysis and Security 29
Data Verification 30
Mineral Processing and Metallurgical Testing 31
Comminution 32
Leach Testwork 32
Bulk Leach for Carbon Loading and Tailings Detoxification 33
Thickening and Filtration 33
Other Testwork 33
Mineral Resource Estimate 34
Mineral Reserve Estimate 37
Mining Methods 39
Open Pit Mining 39
Underground Mining 40
Mine and Production Schedules 41
Recovery Methods 43
Project Infrastructure 44
Market Studies and Contracts 47
Environmental Studies, Permitting and Social or Community Impact 47
Capital and Operating Costs 49
Capital Costs 49
Operating Costs 51
Economic Analysis 51
Interpretation and Conclusions 53
Mineral Resources 53
Mineral Reserves 53
Mineral Processing and Recovery 53
Infrastructure 54
Environmental and Social 54
Recommendations 54
Terms of Reference 55
Qualified Persons and Site Visits 55
Qualified Persons Areas of Responsibility 58
Units and Currency 60
Data Sources 60
Units, Currency and Abbreviations 60
Location 67
Ownership 68
Legal Obligations 70
Environmental Risks, Liabilities and Permitting 71
Environmental Liabilities 72
Permitting 72
Land Access 73
Other Factors 74
Access 75
Physiography 75
Climate 78
Infrastructure 81
Site Layout 82
Project Geology 85
Lithology and Weathering 86
Alteration and Mineralisation 91
Gold Deportment 94
Structure 95
Geophysics 103
Regional Exploration Targets 104
Conclusion 107
Drilling Summary 108
Auger Drilling 111
Surveying 113
Logging 113
Conclusion 114
Sample Dispatch 115
Sample Preparation and Assaying 115
Data Management 116
QAQC Protocol 116
Certified Reference Materials 116
Field Duplicates 118
Blanks 122
Laboratory QAQC 122
Umpire Laboratory Assaying 123
Sampling Precision Comparison 125
Drillhole Direction Analysis 125
Sample Security 126
Introduction 130
Sample Selection 131
Head Assays 137
Comminution Testwork 140
Leach Testwork 144
Grind Size Optimisation 144
Gravity Gold Recovery 145
Cyanide Concentration 147
Oxygen Versus Air Addition 148
Tailings Diagnostic Leach Tests 148
Gravity and Leach Extraction Variability 150
Geometallurgical Relationships 154
Power Demand 154
Reagent Consumption 155
Gold Extraction 158
Materials Handling Testwork 160
Rheology 161
Thickening Testwork 163
Filtration Testwork 164
Bulk Leach Tests 167
Carbon Loading Testwork 168
Cyanide Destruction Testwork 170
Paste Testwork 173
Summary of Metallurgical Interpretation for Design 175
Conclusion 176
Lithological Modelling 177
Domain Modelling 177
Mineralised Domain Statistics 182
Variography 185
Block Models 185
Quantitative Kriging Neighbourhood Analysis 186
Estimation 186
Density 189
Validation 189
Prospect of Eventual Economic Extraction 190
Classification 191
Reasonable Prospects 192
Mineral Resource Estimate 192
Introduction 195
Mineral Reserve Statement 195
Mineral Resources 196
Resource Block Model Conversion 197
Resource Classifications 198
Geotechnical 198
Investigations 198
Open Pit Geotechnical Design 199
Underground Geotechnical Design 206
Hydrogeology 208
Geographical Setting 208
Groundwater Regime 209
Predictive Numerical Groundwater Modelling 210
Geochemical Assessment 211
Groundwater Management 212
Open Pit Optimisation 212
Overview 212
Diluted Mining Block Model 214
Optimisation Parameters 218
Cut-Off Grade 223
Open Pit Underground Transition 224
Optimisation Results 224
Underground Optimisation 229
Introduction 229
Cut-Off Grade 230
Optimisation Parameters 233
Optimisation Results 239
Overall Mining Strategy 240
Mining Method Selection 241
Open Pit Mining 241
Underground Mining 242
Mine Design Basis and Optimisation 244
Open Pit Mine Design 244
Design Criteria 244
Open Pit Mine Designs 248
Waste Rock Dump Design 255
ROM Pad and Stockpile Design 258
Topsoil Stockpiles 261
Underground Mine Design 262
Portal 264
Development Design 266
Mine Schedules 280
Pre-DFS Schedule Evaluation 280
Underground Methodology and Parameters 282
Underground Schedule 283
Open Pit Methodology and Parameters 291
Integrated Open Pit and Underground Schedule 292
Open Pit Mining Operations 302
Open Pit Mining Approach 302
Clearing & Topsoil Removal and Storage 302
Grade Control 303
Drilling and Blasting 303
Load and Haul 304
Open Pit Mine Production Fleet 304
Dewatering and Surface Water Management 305
ROM Management 306
Ore Stockpiling 306
Waste Rock Dump Management 307
Mine Infrastructure 307
Explosives Storage and Management 307
Open Pit Management and Supervision 308
Underground Mining Operations 308
Underground Mining Philosophy 308
Grade Control 309
Drill and Blast 309
Material Transport System 312
Underground Mine Production Fleet 314
Ventilation 315
Paste Fill 338
Ground Stabilisation 343
Dewatering 344
Power Supply 346
Air and Water Supply 349
Communications 350
Escapeways 350
Refuge Chambers 351
Introduction 352
Site Location and Layout 352
Design Criteria Development 354
Process Flowsheet 358
Process Plant Description 360
ROM Pad 360
Crushing Circuit 360
Coarse Ore Stockpile and Reclaim 361
Grinding and Classification Circuit 361
Pebble Crushing 362
Gravity Circuit 362
Pre-Leach Thickening 362
Leach and Adsorption Circuit 363
Desorption 365
Electrowinning and Gold Room 367
Tailings Detoxification 368
Tailings Filtration 368
Paste Feed Production 369
Paste Plant 369
Sampling and Process Monitoring 369
Reagents and Consumables 370
Services 372
Control System 375
Predicted Metallurgical Performance 376
Power Requirements 377
Water Requirements 378
Conclusions 379
Introduction 380
Earthworks 382
Site Access 383
Offices, Warehouses, Workshops and Other Buildings 383
Accommodation Village 384
Power Supply and Distribution 385
Grid Connection 386
Tailings Disposal 387
Tailings Storage Facility Selection and Operation 387
Tailings Storage Facility Design and Construction 388
Tailings Storage Facility Water Balance 390
Surface Water Management 391
Climate 392
Regulatory Framework 393
Flooding Assessment 393
Surface Water Management 394
Site Water Balance 395
Water Supply and Site Water Management 396
Mining Infrastructure 396
Fuel Storage and Supply 397
Paste Plant 398
Other 398
Conclusions 399
Markets 400
Gold Price 400
Contracts 402
Introduction 404
Policies and Regulations 404
Corporate Values - Policy and Governance Commitments 404
Environmental and Social Management System 405
Statutory Regulations and Approvals 406
International Guidelines 408
Environmental and Social Risks 409
Environmental and Social Baseline Studies 409
Risk Assessment Framework 418
Key Identified Risks 419
Health, Safety, Environmental and Social Management Plans 421
Community Health and Safety Management Plan 421
Occupational Health and Safety Management Plan 422
Environmental Management Plan 423
Socio-Economic Management 443
Cultural Heritage Management Plan 448
Closure and Rehabilitation Management Plan 450
Land Acquisition and Resettlement 458
Land Ownership Access Requirements 458
Resettlement Action Plan and Livelihood Restoration 459
Capital Cost Estimate 461
Basis of Estimate 461
Estimate Methodology 462
Estimate Currency and Base Date 471
Contingency Estimate 471
Capital Cost Estimate 471
Execution Readiness Costs 473
Sustaining and Deferred Capital 473
Closure Costs 474
Operating Costs 474
Basis of Estimate and Methodology 475
Estimate Breakdown 479
Mining Costs 479
Labour Costs 485
Power 486
Reagents 487
Consumables 489
Mobile Equipment 489
Maintenance 489
Transport and Logistics 490
General and Administration 490
Tailings Handling 491
Key Assumptions 493
Key Financial Outcomes 494
Sensitivity Analysis 499
Funding Requirement and Strategy 499
Gold Mining in Guinea 501
Regional Gold Mining 501
Artisanal Gold Mining 501
Kouroussa Gold Project 501
Kiniéro Gold Project 502
Reliance on Information from Adjacent Properties 502
Project Implementation 503
Project Phases 503
Project Management Approach 503
Engineering Approach 506
Construction Contracting Strategy 506
Execution Readiness Works 507
Operational Readiness 509
Completions and Commissioning 510
Implementation Schedule 510
Operations 513
Operations Strategy 513
Logistics 513
Ramp-up 513
Human Resources 514
Security 516
Mineral Resources 517
Mineral Reserves 517
Mining Methods 518
Mineral Processing and Metallurgical Testing 518
Recovery Methods 519
Project Infrastructure 519
Environment, Social Impact and Permitting 519
Economic Analysis 520
Risks and Opportunities 520
Risks 520
Opportunities 521
Mine Geotechnical 523
Mining 523
Metallurgical Test Work 523
Site Geotechnical Investigation 523
Hydrogeology 524
Hydrology 524
Environmental and Social 524
Project Implementation 524
LIST OF TABLES
Table 1.1: Comminution Testwork Summary 32
Table 1.2: Mineral Resource Estimate (NEB and BC) 36
Table 1.3: Mineral Resource Estimate (Fouwagbe and Sounsoun) 37
Table 1.4: Bankan Gold Project Mineral Reserve 38
Table 1.5: Proposed Open Pit Mining Fleet 40
Table 1.6: Capital Cost Estimate 50
Table 1.7: Life of Mine Sustaining and Deferred Capital Estimate 51
Table 1.8: Life of Mine Operating Costs 51
Table 1.9: Key Project Metrics 52
Table 1.10: Key Financial Metrics 53
Table 2.1: Qualified Persons Areas of Responsibility 58
Table 2.2: Units and Symbols 61
Table 2.3: Abbreviations 62
Table 3.1: Information Relied Upon from the Company 66
Table 5.1: Annual Rainfall and Evaporation Data 78
Table 7.1: NEB Saprolite versus Fresh Mineralised Composites, Au g/t Statistic 89
Table 7.2: Field Rock Strength Codes, Empirical Tests and UCS Strengths (Barton, 1978) 90
Table 7.3: NEB Sulphide Species Distribution by Grade 93
Table 7.4: BC Sulphide Species Distribution by Grade 93
Table 10.1: Bankan Project Total Drillhole Summary by Year to 31 July 2025 108
Table 10.2: Bankan Project Diamond Drillhole Summary, Resource Areas Only 109
Table 10.3: Bankan Project RC Drillhole Summary, Resource Areas Only 110
Table 11.1: Analytical method summary 115
Table 11.2: Bankan Project QAQC Sample Numbering Plan 116
Table 11.3: Bankan Project QAQC Sample Numbering Plan 117
Table 11.4: BNERC Holes Field Duplicate Statistics 118
Table 11.5:KKORC Holes Field Duplicate Statistics 119
Table 11.6:BNEDD Holes Field Duplicate Statistics 119
Table 11.7:BCKDD Holes Field Duplicate Statistics 119
Table 11.8: Laboratory Original and Duplicate Au g/t Statistics 122
Table 11.9: Laboratory Assay Repeat Au g/t Statistics 123
Table 11.10: Original and umpire Au g/t statistics 123
Table 11.11: Saprolite Composites Au g/t Statistics by Hole Direction 126
Table 11.12: Fresh Composites Au g/t Statistics by Hole Direction 126
Table 13.1: Program 1 Samples (Mintrex) 131
Table 13.2: Program 2 Samples (IMO) 132
Table 13.3: Program 3 Samples (ALS) 134
Table 13.4: Program 3 Variability Sample Head Assays - Part 1 138
Table 13.5: Program 3 Variability Sample Head Assays - Part 2 139
Table 13.6: SmC, BWi, RWi and Ai Results - Full Test 141
Table 13.7: Geopyora Test Results 142
Table 13.8: Program 1 (Mintrex) Grind Size Optimisation Leach Test Results 144
Table 13.9: Program 2 (IMO) Grind Size Optimisation Leach Test Results 145
Table 13.10: Program 1 (Mintrex) Gravity Gold Recovery 145
Table 13.11: Comparison of Leach Extraction with and without Gravity Recovery 146
Table 13.12: NaCN Consumption (kg/t) at Various NaCN Concentration Targets 147
Table 13.13:Air vs Oxygen Sparging Residual Gold (g/t) Comparison 148
Table 13.14: Program 1 Diagnostic Leach Results 149
Table 13.15: Program 2 Diagnostic Leach Results Summary 149
Table 13.16: Summary of Variability Test Results 151
Table 13.17: Lithology Median (P50) Specific Comminution Power Draw 154
Table 13.18: Lithology Blend Operating Grinding Power Estimates 155
Table 13.19: Program 2 Triple Carbon Contact Testwork Results 168
Table 13.20: Program 3 Triple Carbon Contact Test Results 169
Table 13.21: Cyanide Speciation for Detox Feed and Products (Optimised) 171
Table 13.22: Composite Sample for Paste Testwork 173
Table 13.23: Particle Size Distribution of Full Stream and Deslimed Tailings 173
Table 13.24: Paste UCS Test Matrix and Results after 28 Days 174
Table 13.25: Paste Fill Binder Contents GP Cement 175
Table 14.1: Topcut Summary 182
Table 14.2: NEB Mineralisation Domain, Uncut Au g/t Statistics 183
Table 14.3: NEB Mineralisation Domain, Topcut Au g/t Statistics 183
Table 14.4:BC Mineralisation Domain, Uncut Au g/t Statistics 184
Table 14.5:BC Mineralisation Domain, Topcut Au g/t Statistics 184
Table 14.6:Argo Mineralisation Domains Au g/t Statistics 184
Table 14.7: Block Model bankan_ne_202307.mdl Dimensions 185
Table 14.8: Block Model bankan_creek_202307.mdl Dimensions 185
Table 14.9: Block Model fouwagbe_resource202502.mdl Dimensions 186
Table 14.10: Block Model sounsoun202502.mdl Dimensions 186
Table 14.11: NEB Kriging Estimation Parameters 186
Table 14.12: BC Kriging Estimation Parameters 187
Table 14.13: Argo Kriging Estimation Parameters 188
Table 14.14: NEB Au g/t Validation Statistics 189
Table 14.15: BC Au g/t Validation Statistics 190
Table 14.16: Preliminary Pit Optimisation Parameters 190
Table 14.17: Mineral Resource Estimate (NEB and BC) 193
Table 14.18: Mineral Resource Estimate (Fouwagbe and Sounsoun) 194
Table 15.1: Bankan Gold Project Mineral Reserves 196
Table 15.2: Resource Model Parameters 197
Table 15.3: Bankan Resource Model Parameters 197
Table 15.4: NEB Pit Geotechnical Design Parameters 200
Table 15.5: BC Pit Geotechnical Design Parameters 203
Table 15.6: GBE Pit Geotechnical Design Parameters 206
Table 15.7: NEB Underground Geotechnical Stope Design Parameters 207
Table 15.8: NEB Underground Geotechnical Ground Support and Reinforcement Requirements 208
Table 15.9: Mixing Width Calculation by Deposit 217
Table 15.10: Global Resource Ore Loss and Dilution (Weighted Average) 218
Table 15.11: Overall Slope Angle Calculation 219
Table 15.12: Fixed Costs ($/t mined) 220
Table 15.13: Drill and Blast Costs ($/t mined) 220
Table 15.14: Load and Haul (incl. Ancillary) by Bench by Pit ($/t mined) 221
Table 15.15: Ore Related Costs ($/t ore) 222
Table 15.16: Revenue Parameters 223
Table 15.17: Mineral Reserve Cut of Grade - Open Pit Mining 224
Table 15.18: Open Pit/Underground Transition Optimisation Results - Physicals 225
Table 15.19: Open Pit/Underground Transition Optimisation Results - Financials 225
Table 15.20: Open Pit/Underground Transition Optimisation Results - Sensitivity to Mining Cost 225
Table 15.21: Open Pit Only Optimisation Results - Physicals 226
Table 15.22: Open Pit Only Optimisation Results - Financials 227
Table 15.23: Mining Costs Calculations 231
Table 15.24: Cut-Off Grade Inputs 231
Table 15.25: Underground Cut-off Grade Sensitivity 232
Table 15.26: Stope Optimisation Input Parameters 233
Table 16.1: Pit Wall Design Criteria 244
Table 16.2: Design Ramp and Roads Widths 245
Table 16.3: Waste Rock Dump Design Criteria 248
Table 16.4: Optimisation Shell and Pit Design Comparison 255
Table 16.5: Dilution and Ore Loss Within Pit Designs 255
Table 16.6: Waste Dump Capacities 258
Table 16.7: Overview of Bankan Development Design 269
Table 16.8: Stope Parameters for Different Level Spacings 273
Table 16.9: Stope Shape Calculated Hydraulic Radius 277
Table 16.10: Stopes Shapes Tonnes and Grade by Mining Method 280
Table 16.11: Bankan Mining Recovery Factors 283
Table 16.12: Scheduling Parameters - Resource Rates 286
Table 16.13: Scheduling Parameters - Task Rates 286
Table 16.14: Underground Development Schedule 288
Table 16.15: Vertical Development Metres 289
Table 16.16: Service Holes Schedule 289
Table 16.17: Paste Fill Requirements 290
Table 16.18: Underground Ore Production 290
Table 16.19: Project LOM Schedule - Total Mined Tonnes 297
Table 16.20: Project LOM Schedule - Material Movement by Mining Stage 297
Table 16.21: Life of Mine Schedule - Mill Feed by Lithology and Production 300
Table 16.22: Drill and Blast Design Parameters 304
Table 16.23: Proposed Open Pit Mining Fleet 305
Table 16.24: Drill Density per Mining Method 310
Table 16.25: Underground Mine Production Fleet 315
Table 16.26: Summary of Ventilation Design Criteria 316
Table 16.27: Machine DEE Dilution Airflow Requirements 318
Table 16.28: Primary Fan Specification 326
Table 16.29: Heat Design Criteria 331
Table 16.30: Monthly Ambient Temperatures 332
Table 16.31: Paste Strengths by Dimension (Minefill Services, 2025) 341
Table 17.1: Key Process Design Criteria and Equipment Sizing 355
Table 17.2: Project Electrical Power Demand 378
Table 18.1: Estimated Site Load 385
Table 18.2: Paste Plant Design Criteria 398
Table 20.1: Summary of the Environmental and Social Baseline of the Project Area 410
Table 20.2: Key Management Measures for Air Quality and GHG 425
Table 20.3: Key Management Measures for Water Management 428
Table 20.4: Key Management Measures for Impacts to Biodiversity 432
Table 20.5: Key Management Measures for Traffic and Transport 435
Table 20.6: Key Management Measures for Waste Management 439
Table 20.7: Key Management Measures for Socio-Economic Impacts 444
Table 20.8: Key Management Measures for Cultural Heritage 449
Table 20.9: Closure and Rehabilitation Plan for the Project Infrastructure 452
Table 21.1: Capital Cost Estimate Methodology 463
Table 21.2: Basis of Deliverables and General Project Data Requirements 466
Table 21.3: Foreign Exchange Rates 471
Table 21.4: Capital Cost Estimate 472
Table 21.5: Execution Readiness Costs 473
Table 21.6: Life of Mine Sustaining and Deferred Capital Estimate 474
Table 21.7: Life of Mine Operating Costs 475
Table 21.8: Operating Cost Methodolgy 476
Table 21.9: Open Pit Mining Unit Rates 480
Table 21.10: Open Pit Owner Supplied Rates 481
Table 21.11: Underground Mining Unit Rates 483
Table 21.12: Underground Owner Supplied Rates 484
Table 21.13: Labour Costs 486
Table 21.14: Power Station Power Costs 487
Table 21.15: Reagent Cost and Consumption 488
Table 21.16: Consumables 489
Table 21.17: General and Administration 491
Table 21.18: Tailings Rehandle Fleet and Costs to TSF 492
Table 21.19: Tailings Rehandle Unit Rates 492
Table 22.1: Key Financial Model Assumptions 493
Table 22.2: Key Project Outcomes 495
Table 22.3: Detailed LOM Production and Cashflow 498
Table 24.1: Schedule Float 511
Table 24.2: Bankan Project Production Ramp-up 514
Table 24.3: Bankan Operations Staff 515
Table 25.1: Key Risks and Mitigating Strategies 521
Table 26.1: Recommended Execution Readiness and FEED Program Costs 525
LIST OF FIGURESFigure 1.1: Project LOM Schedule - Total Material Mined 42
Figure 1.2: Project LOM Schedule - Mill Feed by Lithology and Grade 42
Figure 1.3: Project LOM Schedule - Mill Feed Contained Gold by Source 43
Figure 1.4: Project LOM Schedule - Mill Feed Recovered Gold 44
Figure 1.5: Overall Site Layout 46
Figure 4.1: Project Location (PDI 2025) 67
Figure 4.2: Project Region (PDI 2025) 68
Figure 4.3: Project Permits (PDI 2025) 70
Figure 5.1: View Towards the Niger River from the Project Area (PDI 2024) 76
Figure 5.2: Terrain and Drainage Plan 77
Figure 5.3: Average Rainfall and Temperature (MetoBlue 2025) 79
Figure 5.4: Wind Rose for Kouroussa (MetoBlue 2025) 79
Figure 5.5: Overall Site Layout 83
Figure 7.1: Bankan Project Interpreted Geology, Resources and Targets (PDI 2024) 86
Figure 7.2: Typical Lateritic Weathering Profile (Chardon, Grimauld, Beauvaise, & Bamba, 2018) 87
Figure 7.3: BNED0087 Laterite Zone 88
Figure 7.4: BNEDD0087 Mottled Zone 88
Figure 7.5: BNEDD0087 Saprolite Zone 88
Figure 7.6: BNEDD0087 Contact Between Saprolite Zone (upper) and Saprock Zone (Lower) 88
Figure 7.7: BNEDD0087 Fresh Zone 89
Figure 7.8: Proportions of Rock Strength Codes by Logged Weathering 91
Figure 7.9: Gold Grain Size Distribution from 174 Individual Grains 94
Figure 7.10: Left: BNEDD0088 325.6m; Right: BNERD0073 30m 95
Figure 7.11: Left: BNEDD0106B 637.02m; Right: BNERD0107 553.42m 95
Figure 7.12: Left: BNERD0098 386.72m, Rotated Augen; Right: BNERD074 318.65, Pressure Shadows around Pyrite 96
Figure 7.13: BNEDD0086 Main Shear 320.0-340.1m, 20.1m @ 0.48g/t 98
Figure 7.14: 10350mRL Geology Interpretation 99
Figure 7.15: 10250mRL Geology Interpretation 99
Figure 7.16: 10150mRL Geology Interpretation 100
Figure 7.17: 10050mRL Geology Interpretation 100
Figure 8.1: Location and Geology of the Siguiri Basin (Lebrun, Thébaud, Miller, Roberts, & Evans, 2017)
. 102
Figure 9.1: IP Gradient Array Images for NEB (resistivity left, chargeability right) Overlain with the NEV Optimised Resource Pit Shell and the >0.2 g/t Auger Anomaly Contours (PDI 2021) 104
Figure 9.2: Near Bankan Targets and Drilling Results (PDI 2024) 105
Figure 9.3: Argo Targets and Drilling Results (PDI 2024) 106
Figure 9.4: Bokoro Targets and Drilling Results (PDI 2024) 107
Figure 10.1: Bankan Project Drillhole Resource Plan; Resource and Non-Resource (L) and by Type (R)
. 109
Figure 10.2: Auger Drill Rig (PDI 2024) 112
Figure 10.3: Auger Drill Result Contours around NEB and BC Deposits (PDI 2021) 113
Figure 11.1: BNERC Holes Field Duplicates Scatterplot 120
Figure 11.2: KKORC Holes Field Duplicates Scatterplot 120
Figure 11.3: BNEDD Holes Field Duplicates Scatterplot 121
Figure 11.4: BCKDD Holes Field Duplicates Scatterplot 121
Figure 11.5: Original and Umpire Laboratory QQ' Plot 124
Figure 11.6: Original and Umpire Laboratory QQ' Plot <10 g/t 124
Figure 11.7: Ranked ARD Plot of Duplicate Sample Pairs 125
Figure 13.1: Shear and Tonalite Lithology Transition, BNEDD0147 136
Figure 13.2: Saprolite Lithology, BNEDD0147 136
Figure 13.3: Mafic Lithology, BNEDD0204 137
Figure 13.4: Head Grade Analysis, Au vs Cu 140
Figure 13.5: Head Grade Analysis, S vs Cu 140
Figure 13.6: Deleterious Element, by Sample 140
Figure 13.7: Axb Comparison - SMC vs. Geopyora 143
Figure 13.8: Program 2 Bulk Leach Gold Extraction with Decreasing NaCN Concentration 148
Figure 13.9: Copper in Solution Histogram 153
Figure 13.10: Iron in Solution Histogram 154
Figure 13.11: Cyanide Consumption by Lithology 156
Figure 13.12: Cyanide Consumption versus Copper in Solution 156
Figure 13.13: Lime Consumption by Lithology 157
Figure 13.14: 24-Hour Gold Extraction versus Head Grade by Deposit 158
Figure 13.15: 24-Hour Gold Extraction versus Head Grade by Lithology 158
Figure 13.16: 24-Hour Extraction versus Head Grade 159
Figure 13.17: Modelled vs Measured Au Extraction 160
Figure 13.18: Viscosity versus Shear Rate for Fresh Ore 161
Figure 13.19: Viscosity versus Shear Rate for 25% Saprolite / 75% Fresh Ore 162
Figure 13.20: Viscosity versus Shear Rate for 50% Saprolite / 50% Fresh Ore 162
Figure 13.21: Viscosity versus Shear Rate for 75% Saprolite / 25% Fresh Ore 163
Figure 13.22: Viscosity versus Shear Rate 100% Saprolite 163
Figure 13.23: 100% Saprolite Sample in (a) the Chamber and (b) the Top View of the Cake 165
Figure 13.24: 50% Saprolite Sample from 40mm Chamber @15.9% Moisture 166
Figure 13.25: Moisture versus Filtration Capacity - 50mm Chamber 167
Figure 13.26: Equilibrium Gold Loading Curves 170
Figure 13.27: Cyanide Speciation Definitions 172
Figure 14.1: 10350mRL NEB Medium-Grade and High-Grade with Shear Zones 178
Figure 14.2: 10250mRL NEB Medium-Grade and High-Grade with Shear Zones 179
Figure 14.3: 10150mRL NEB Medium-Grade and High-Grade with Shear Zones 179
Figure 14.4: 10050mRL NEB Medium-Grade and High-Grade with Shear Zones 180
Figure 14.5: BC Lithological and Domain Model with Red, Main Shear; White, Second Order Shear, Purple, Tonalite and Pink, Medium-Grade Domain 181
Figure 14.6: Fouwagbe Interpreted Mineralisation Zone (PDI 2025) 181
Figure 14.7: Sounsoun Interpreted Mineralisation Zones (PDI 2025) 182
Figure 15.1: NEB Pit Domains (Representative View Looking North) 200
Figure 15.2: NEB Pit Domain A Wall Design Parameters 201
Figure 15.3: NEB Pit Domain B Wall Design Parameters 202
Figure 15.4: BC Geotechnical Pit Domains (Representative View Looking North) 203
Figure 15.5: BC Pit Domain A Wall Design Parameters 204
Figure 15.6: BC Pit Domain B Wall Design Parameters 205
Figure 15.7: GBE Pit Wall Design Parameters 206
Figure 15.8: Whittle™ Mining Sequence 214
Figure 15.9: Regularisation Process to a Parcel Model (Orelogy 2025) 215
Figure 15.10: Determination of Mixing Zone (Orelogy 2025) 216
Figure 15.11: Swapping of Material within Mixing Zone (Orelogy 2025) 216
Figure 15.12: Open Pit Only Optimisation Results - Tonnes / Value Curves 228
Figure 15.13: Plan and Section Comparing "No Underground" Shell 30 to "Open Pit/Underground Transition" Shell 36 229
Figure 15.14: Vertical Slice Method Applied to a Vertical Orebody (Orelogy 2025) 230
Figure 15.15: NEB Orebody Geometry 230
Figure 15.16: Cut-off Grade Sensitivity Analysis 233
Figure 15.17: Underground Grade and Tonnage versus Cut-off Grade 235
Figure 15.18: Indicated Mineral Resources Tonnes and Grade versus Cut-off Grade 236
Figure 15.19: Inferred Mineral Resources Tonnes and Grade versus Cut-off Grade 236
Figure 15.20: Single Lift Scenario (Orelogy 2025) 237
Figure 15.21: Double Lift Scenario (Orelogy 2025) 238
Figure 15.22: Stope Shape Results Looking East 239
Figure 16.1: Open Pit Mining Cycle (Orelogy 2025) 241
Figure 16.2: Access to Underground from the GBE Open Pit Looking East 242
Figure 16.3: Dual-Lane In-Pit Ramp Layout 246
Figure 16.4: Single-Lane In-Pit Ramp Layout 246
Figure 16.5: Dual-Lane Ex-Pit Road Layout 247
Figure 16.6: Waste Rock Dump Design Criteria (Construction and Final Landform) 248
Figure 16.7: GBE Pit Design 250
Figure 16.8: Cross Section through GBE Pit Design (10370E) 250
Figure 16.9: NEB Stage 1 Pit Design 251
Figure 16.10: NEB Stage 2 Pit Design 252
Figure 16.11: NEB Stage 3 Pit Design 253
Figure 16.12: NEB Pit Cross Section 253
Figure 16.13: BC Pit Layout 254
Figure 16.14: GBE Waste Rock Dump Layout 256
Figure 16.15: NEB Waste Rock Dump Layout 257
Figure 16.16: BC Waste Rock Dump Layout 258
Figure 16.17: GBE Pit Infrastructure Layout 259
Figure 16.18: GBE Underground Stockpile Traffic Flow 260
Figure 16.19: ROM Pad Layout 260
Figure 16.20: NEB/GBE Topsoil Stockpile Layout 261
Figure 16.21: BC Topsoil Stockpile Layout 262
Figure 16.22: GBE Pit and Underground Mine Design - Looking East 263
Figure 16.23: Plan view of GBE Pit and Underground Mine Design 264
Figure 16.24: PFS BoxCut and Decline Looking North 265
Figure 16.25: DFS GBE and Decline Access Looking East 265
Figure 16.26: Haulage and Ventilation Portal Locations - Plan View GBE Pit 266
Figure 16.27: Overview of Bankan Underground Development Design - Looking South 268
Figure 16.28: Typical Level Layout (9960 mRL) - Plan View 271
Figure 16.29: Underground Mine Surface Infrastructure 272
Figure 16.30: Vertical Development Elevation - Looking Northwest 273
Figure 16.31: Level Spacing - Cross Section 274
Figure 16.32: Stope Shapes Generated using Deswik.SO - Looking West 275
Figure 16.33: Stope Shapes Generated using Deswik.SO - Plan View 276
Figure 16.34: Stope Shapes Divided into the Different Geotechnical Zones - Looking West 277
Figure 16.35: Examples of Split Stopes on Different Level Intervals - Plan View 278
Figure 16.36: TLHOS vs LLHOS Decision Making - Plan View 278
Figure 16.37: Stope Shapes Grouped Based on Mining Method After Splitting - Plan View 279
Figure 16.38: Stope Shapes Grouped by Mining Method After Splitting - Looking East 280
Figure 16.39: Stopes, Sill Pillars and Crown Pillars - Cross Section View 283
Figure 16.40: Stoping Sequence in Panels - Looking East 285
Figure 16.41: Stopes Divided by Primary and Secondary - Looking East 286
Figure 16.42: Project LOM Schedule - Total Material Mined 293
Figure 16.43: Project LOM Schedule - Mill Feed by Lithology and Grade 293
Figure 16.44: Project LOM Schedule - Mill Feed Tonnes by Source 294
Figure 16.45: Project LOM Schedule - Mill Feed Contained Gold by Source 294
Figure 16.46: Project LOM Schedule - Mill Feed Recovered Gold 295
Figure 16.47: Project LOM Schedule - Stockpile Balances by Lithology 296
Figure 16.48: Firing Sequence (Orelogy 2025) 310
Figure 16.49: Typical Production Ring Configuration for Transverse Stopes (Orelogy 2025) 311
Figure 16.50: Typical Production Ring Configuration for Longitudinal Stopes (Orelogy 2025) 311
Figure 16.51: Surface Layout 312
Figure 16.52: Level Layout Showing Loading Points - 9980 mRL 314
Figure 16.53: Project Airflow Demand 319
Figure 16.54: Primary Ventilation System - Section View Looking East 321
Figure 16.55: Primary Ventilation System - Plan View 322
Figure 16.56: Photo of an Auxiliary Fan mounted on a Support Structure (Mintek Australia Pty Ltd) 323
Figure 16.57: Secondary Ventilation Layout - Development Phase (Orelogy 2025) 324
Figure 16.58: Secondary Ventilation Layout - Production Phase (Orelogy 2025) 324
Figure 16.59: Ventilation Duct Clearance (Orelogy 2025) 325
Figure 16.60: Airflow Simulation using Ventsim® Software 326
Figure 16.61: Temporary Primary Fan Installation - Example Fan Curve (ClemCorp Australia Pty Ltd) 327 Figure 16.62: Permanent Primary Fan Installation - Example Fan Curve (Mintek Australia Pty Ltd) 328
Figure 16.63: Operational Auxiliary Fan Requirements 330
Figure 16.64: Bankan Gold Project Monthly Air-Cooling Requirements 333
Figure 16.65: Bankan Gold Project Heat Load Distribution 334
Figure 16.66: Bankan Gold Project Heat Load Balance 335
Figure 16.67: General Arrangement Drawing of a Typical Bulk Air Cooler (BAC) (IWC 2025) 336
Figure 16.68: General Arrangement Drawing of a Typical Refrigeration Plant (IWC) 337
Figure 16.69: Location of 4.5 MW BAC Refrigeration Plant - Plan View 338
Figure 16.70: Undercut Stopes in Red - Looking East 339
Figure 16.71: Paste fill Strengths and Mine Sequence (Orelogy 2025) 340
Figure 16.72: Paste Fill (Line in Pink) 341
Figure 16.73: Paste Fill Plant Location 342
Figure 16.74: Flow Model 10140 mRL Level 343
Figure 16.75: Primary Pump Stations and Dewatering Route 345
Figure 16.76: Photo of a Typical Underground Pump Station with Capacity of 60 L/s (Challenge Pumps Pty Ltd) 346
Figure 16.77: Underground Power Reticulation Backbone - Cross Section View 347
Figure 16.78: Surface Power Required Areas 348
Figure 16.79: Annual Connected Load Bankan Underground 349
Figure 16.80: Annual Power Usage Bankan Underground in GWh 349
Figure 16.81: Escapeway Route (Shown in Green) 350
Figure 17.1: Overall Site Layout 353
Figure 17.2: Process Flowsheet 359
Figure 17.3: Life of Mine Schedule - Mill Feed by Lithology and Grade 376
Figure 17.4: Gold Production and Grade 377
Figure 18.1: Overall Site Layout 381
Figure 18.2: TSF and Tailing Water Storage Dam 388
Figure 18.3: TSF Water Balance Probabilistic Analysis Results 391
Figure 18.4: Flood Modelling Outcomes 1:100 RI plus Climate Change Event 394
Figure 19.1: Four Year Historical Gold Price 401
Figure 19.2: Consensus Gold Price Forecast 402
Figure 20.1: Integrated Management System (PDI 2024) 406
Figure 20.2: ESIA Process (PDI 2024) 419
Figure 21.1: Fixed Open Pit Contractor Costs over LOM 481
Figure 21.2: Open Pit Diesel and Explosives Usage over LOM 482
Figure 21.3: Fixed Underground Contractor Costs over LOM 484
Figure 21.4: Underground Owner Supplied Diesel and Explosives Costs over LOM 485
Figure 22.1: Gold Production and Grade 496
Figure 22.2: All-in Sustaining Cost per Oz 496
Figure 22.3: Project Cash Flow 497
Figure 22.4: Post Tax NPV5% Sensitivities 499
Figure 24.1: Owners Team Organisation Structure 505
Figure 24.2: Pre-Production Workforce Ramp-up 509
Figure 24.3: Summary Project Implementation Schedule 512
Figure 24.4: High Level Organisation Chart 514
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Introduction, Location and Ownership
This Report was prepared for Predictive Discovery Limited (PDI or the Company) on the Bankan Gold Project, Guinea (the Project). This Report was prepared for the purposes of reporting on the definitive feasibility study (DFS) released to the Australian Stock Exchange on 25 June 2025 in accordance with the Joint Ore Reserves Committee (JORC) "Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves" and CIM 2014 Definition Standards to align with the continuous disclosure of Exploration Results, Mineral Resources and Mineral Reserves in accordance NI 43-101.
The effective date of this Report is July 31, 2025.
The Project is located in the northeast part of Guinea, approximately 450 km east-northeast of Guinea's capital city, Conakry, in the Kouroussa Prefecture. The Project is located 75 km northwest of the regional city of Kankan and 7 km southwest of Kouroussa town.
The main Project area lies within the Peripheral Zone of the Upper Niger National Park with the NEB and BC deposits approximately 21 km and 18 km, respectively, away from the closest point of the Core Conservation Area.
The Project comprises four contiguous Permis de Recherce Industrielle (Or) (exploration permits), which cover a combined area of 356 km2 and are located between 9 51'00"W and 10 03'24"W and between 10 32'26"N and 10 52'00"N.
PDI's four exploration permits relating to the Project and its wider exploration potential, comprise:
Kaninko gold exploration permit, issued by order no. A/2019/5784/MMG in favour of PDI's wholly owned local subsidiary Mamou Resources SARLU (Mamou) on 3 October 2019, covering a 98.22 km² area.
Saman gold exploration permit, issued by order no. A/2020/1835/MMG in favour of Mamou on 11 June 2020, covering a 99.78 km² area.
Bokoro gold exploration permit, issued by order no. A/2020/2561/MMG in favour of PDI's wholly owned local subsidiary Kindia Resources SARLU on 9 September 2020, covering a
99.98 km² area.
Argo gold exploration permit, issued by order no. A/2018/7628/MMG in favour of Argo Mining SARLU on 24 October 2018 (in which PDI is a shareholder and has the right to progressively earn 90% by payment of US$100,000 and acquire the remaining 10% at a decision to mine in exchange for a 2% net smelter royalty), covering a 57.54 km² area.
The main Project area, and all the Mineral Resources on which this DFS is based, are situated on parts of the Kaninko and Saman exploration permits.
On 31 January 2025, PDI and Mamou submitted exploitation permit applications for 50% of the Kaninko and Saman permit areas to the Ministry of Mines and Geology (MMG) and Centre for the Promotion of the Development of Mining (CPDM) in accordance with Guinean mining law. PDI has indicated that the applications are at an advanced stage and are still being processed. PDI is not aware of any immediate obstacles to the granting of the exploitation permits.
PDI submitted renewal applications for the Argo and Bokoro exploration permits in 2021 and 2023 respectively, and has relied on Article 78 of the Guinean Mining Code that allows for permits to be extended automatically until the date of renewal. PDI has been made aware that, on 26 May 2025, the MMG announced the revocation of over 100 exploration permits, including the Argo exploration permit (which hosts the Fouwagbe and Sounsoun Deposits) and the Bokoro exploration permit. PDI has not received any formal communication from the Guinean government on the matter and intends to work diligently with the MMG to achieve the granting of the renewals.
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History
In late 2018 PDI commenced work in the Kaninko area in the Siguiri Basin. Field visits identified widespread artisanal workings consisting of extensive pitting into weathered bedrock with shallow surficial workings in lateritic cover material extending for hundreds of metres away from the pitted areas, in what were later to be identified as the NEB and BC deposits.
PDI's initial field work included BLEG stream sediment geochemistry, rock chip sampling and geological mapping followed by twelve vertical channel samples. This initial program was followed up by a second program of systematic channel sampling of saprolite exposures.
In early 2020, a program of 3,178 m of shallow power auger drilling and 490 lineal metres of trenching was completed at NEB and BC, with mineralisation identified across a broad zone This program was followed up by an aircore and reverse circulation drilling program, with further auger drilling extending the strike length of NEB.
A maiden mineral resource estimate was completed for the Project in September 2021 comprising an Inferred Mineral Resource of 72.8 Mt at 1.56 g/t Au for 3.65 Moz of contained gold. On the 1st of August 2022 additional drilling was used to update the Inferred Mineral Resource estimate to 79.5 Mt at 1.63 g/t Au for 4.2 Moz of contained gold.
Based on an infill drilling program through the second half of 2022 the mineral resource estimate confidence was improved and an updated mineral resource estimate was announced on 6 February 2023 including an Open Pit Indicated Mineral Resource of 42.7 Mt at 1.27 g/t Au for 1.75 Moz contained gold at NEB along with a further Open Pit Inferred Mineral Resource of 24.7 Mt at 2.23 g/t Au for 1.77 Moz contained gold and an Underground Inferred Mineral Resource at NEB of 2.2 Mt at
4.75 g/t for 335 koz contained gold. An Inferred Mineral Resource of 7.2 Mt at 1.42 g/t for 331 koz of contained gold was announced for the BC deposit.
Continued drilling at the Project led to an announcement on 7 August 2023 an increase to these mineral resources to an estimated 100.5 Mt at 1.66 g/t Au for 5.4 Moz of contained gold with approximately 77% being in the Indicated Mineral Resource category. Based on this mineral resource estimate, PDI completed a pre-feasibility study (PFS) which included the announcement of a maiden Mineral Reserve for the Project, consisting of open pit and underground ore from NEB and open pit ore from BC, of 57.7 Mt at 1.64 g/t for 3.05 Moz of contained gold. All Mineral Reserves were in the Probable Mineral Reserves category.
Other than artisanal scale gold mining, which is not material to the Mineral Resources or Mineral Reserves, there has been no production from the Property.
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Geological Setting and Mineralisation
The Project is hosted by greenstones in the southwest margin of the Siguiri Basin, in upper Guinea. The Siguiri Basin contains metasediments and related volcanic and plutonic rocks of the early Proterozoic Birimian supergroup, which hosts most of West Africa's gold deposits. The gold deposits within the region are principally orogenic lode deposits. Prolonged weathering has led to extensive lateritic duricrusts and deep saprolite profiles. Vertical remobilisation of gold during lateritic weathering is common, and primary gold deposits are often overlain by lateritic or supergene gold deposits.
The Project area is deeply weathered, with a thick saprolite and a pisolitic and nodular lateritic cover which hosts remobilised gold, generally above the primary deposits or dispersed a few tens of metres laterally. Outcrops are sparse, and the underlying bedrock geology is known largely from regional scale geophysics and drilling completed by PDI.
Regionally, mineralisation has been focussed on the intersection of north-northwest striking and northwest striking structures on the margin of a regional granitic batholith. Numerous anastomosing north-northeast striking structures have been interpreted from the aeromagnetic data. Smaller granitic intrusions in the greenstones are structurally controlled and provide evidence for significant heat and fluid flow late in the orogenic history, likely to be part of the gold mineralisation process.
These granitic intrusions partially host the two Project main deposits. NEB has been developed at the hanging wall contact of a small tonalitic intrusion, structurally controlled by a north-northwest striking shear (main shear zone or STMZ), which is part of a network of anastomosing north-northwest to north-northeast striking structures. The NEB deposit includes a small satellite deposit, GBE, located approximately 250 m north of the main NEB deposit.
In the footwall, a very well developed second order shear, 3 m to 5 m thick, (STSZ01) has very similar structure and alteration characteristics to the STMZ and forms a step over, or jog, from the STMZ to a more weakly developed structure and hence it is a locus for dilation and fluid flow associated with mineralisation. The STSZ01 nearly outcrops, whereas the STMZ terminates below the surface above its intersection with STSZ01. This fault duplex is interpreted to represent a soft-linked overlapping shear system, where a component of strain is accommodated by rotation or folding between the main bounding shear segments, as well as at the termination of the segments.
Below the STSZ01 shear, four other parallel structures have been interpreted with similar relationships to the STMZ, however, these are less well constrained by drilling and, hence, have a greater degree of uncertainty in their location and extent.
Higher grades are found in and on the immediate footwall of the STMZ, with lower grade mineralisation in both the tonalitic footwall and the greenstone hanging wall. Mineralisation comprises wide zones of structurally controlled chlorite, silica and sericite alteration with associated pyrite and quartz veining.
Sulphide mineralisation largely comprises pyrite with minor chalcopyrite. In the altered felsic igneous rocks, the sulphide mineralisation is generally associated with the later stage veining, with minor amounts disseminated through the rock texture. In NEB, higher grade mineralisation is characterised by higher pyrite and covellite, and arsenopyrite and sphalerite contents. Low-grade mineralisation
lacks covellite, galena, sphalerite, and bismuth species. Other sulphides that have been noted include tennantite-tetrahedrite, hessite, gersdorfitte, bornite and cobaltite. Generally sulphide content is low.
BC is hosted in the carapace of a small tonalitic intrusion, which has intruded a structurally complex greenstone sequence of clastic and carbonate metasediments, volcanics and marbles. The structural controls for BC are much less well understood. From the drillhole logging, two shears have been interpreted. A major one dipping moderately to the southwest and a second order structure dipping moderately to the northeast. These appear to constrain both the small tonalite intrusion and the mineralisation that is localised in the carapace of the intrusion. Foliations generally dip parallel to the major shear, whereas the veins have several preferred orientations and a greater scatter than the veins at NEB. Bedding planes and contacts broadly dip parallel to the foliations and shears.
The weathered profile in the Project area comprises:
Cemented ferricrete layer, composed of in-situ or transported ferruginous concretions in a ferruginous matrix.
Mottled clay layer, composed of variably ferruginous residual clays formed by intense weathering and consequent profile collapse.
Saprolite zone, composed of highly weathered bedrock, where there has not been sufficient leaching to initiate the collapse of the profile, and original rock textures are recognisable even though most original rock forming minerals have been weathered to clays. There may be a transition or saprock zone at the base of the saprolite zone into the fresh zone, where weathering is either patchy or restricted to favourable structures. Levels greater than 40% fresh rock defines this saprock zone.
Underlying essentially un-weathered fresh zone.
The complete laterite profile is preserved at NEB under a ridge capped with resistant ferricrete. At BC, recent erosion has incised the currently active river valley and the mottled zone and saprolite are largely exposed at the surface in the artisanal workings with a thin veneer of transported soil and alluvium elsewhere. A few small patches of remnant ferricrete have also been identified.
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Exploration
Due to the deep weathering, transported cover and lack of outcropping rock, the most effective exploration methods have proved to be geophysical and geochemical vectoring, followed up by drill sampling.
Following the NEB discovery, PDI completed a series of early-stage exploration programs, including broad spaced auger drilling and a helicopter-borne magnetic and radiometric survey. The aeromagnetics identified a major 35km-long north-northwest structural corridor with the potential to host multiple orogenic gold discoveries. Structural targets identified using the aeromagnetics have been progressively followed up with power auger and aircore (AC) drilling. The strategy to date has been to undertake wide-spaced auger drilling covering the structural targets, typically 320 m by 80 m spacing, followed by closer spaced infill where encouraging gold results have been obtained (generally plus 0.25g/t composite values in saprolite to depths of around 20 m). AC drilling has then followed up the encouraging auger results, typically with pairs of scissor holes to help assess the orientation of the gold mineralisation.
These samples are useful for producing geochemical anomalies, however due to the open hole and non-representative sampling, are not used for resource estimation.
PDI has also completed a comprehensive petrophysics and ground geophysics program at NEB. The petrophysics study of the NEB drill core was designed to calibrate the detailed ground geophysical orientation program.
The ground geophysical techniques selected were gradient array induced polarisation ("GAIP") and pole dipole induced polarisation ("P-DIP"), magnetics and gravity with P-DIP methods proving the most effective in geophysically finger-printing the NEB deposit, with elevated chargeability (attributed to sulphide mineralisation) and elevated resistivity (attributed to silica alteration).
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Drilling
Drilling completed at the Project comprises aircore (AC), reverse circulation (RC), reverse circulation grade control (RCGC) and diamond core (DDH) holes, with some deeper diamond holes having a RC pre-collar in expected waste and core thereafter. For the Mineral Resource Estimate for the NEB and BC deposits, announced in August 2023, only the DDH and RC holes were used as AC samples are not considered representative. Drillhole spacing is variable, typically 40 m spacing on 40 m sections in the upper parts of the deposits and spacings as much as 100 m at the lower fringes.
The total drilling incorporated into the Mineral Resource estimates for the NEB and BC deposits comprises:
NEB Deposit:
26,341 m RC across 209 holes.
84,162 m DDH or RC pre-collar with DDH across 202 holes.
BC Deposit:
2,321 m RC across 20 holes.
11,536 m DDH or RC pre-collar with DDH across 59 holes.
An additional 394 AC holes for 18,684 m which were used to supplement the RC and DDH holes for geological interpretation.
Drilling results after the cutoff dates for the mineral resource estimates have been reviewed but not yet modelled. This includes infill drilling at both NEB and BC. The results of the additional data are in line with the resource models and are not expected to significantly change the mineral resource estimates or classification.
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Sample Preparation, Analysis and Security
Samples have been assayed by fire assay at a range of commercial laboratories in West Africa with most of the recent samples having been assayed at SGS in Bamako, Mali. PDI has implemented a quality assurance/quality control (QAQC) program for exploration and resource evaluation drilling and sampling at the Project, comprising monitoring of:
Analytical data accuracy using certified reference materials (CRMs) and umpire laboratory assaying.
Analytical data precision using field and laboratory duplicate and repeat samples.
Potential for contamination during sample preparation using blanks.
No significant issues were noted with the CRMs, blanks, laboratory duplicates or umpire assaying. From the field duplicates, the precision of the sampling is reasonable, with the poorest precision in the core duplicate pairs, suggesting that there is a moderate to high fundamental nugget factor in the mineralisation.
Based on the data assessment, the Qualified Person considers the entire dataset acceptable for resource estimation subject to the preceding comments regarding the analytical accuracy and precision.
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Data Verification
PDI has been developing the resources since 2019. The Qualified Person has visited the site on four occasions, from the 10th to the 15th June 2022, from the 10th to the 21st November 2022, from the 11th to the 27th January 2023 and from 28th August 2024 to the 5th September 2024. During these visits, the following were inspected:
General site layouts.
DDH, RC, AC and auger drilling.
Drillhole setup.
DDH core orientation and markup.
DDH core logging and sampling.
Density measurement procedure.
Point Load Test measurement procedure.
X-Ray Fluorescence measurement procedure.
RC, RC and auger logging and sampling.
Sample dispatch.
DDH core and RC retention bag storage.
Pulp storage.
Review of selected core intervals and comparison with assaying results. Detailed technical discussions with PDI staff were also conducted.
The Qualified Person has checked a selection of the original assay certificates against the database and not identified any errors.
The drilling, sampling, assaying, quality assurance, sample security and data handling procedures at the Project are well designed and are well implemented; they are capable of producing a reliable dataset that is fit for purpose for Mineral Resource estimation.
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Disclaimer
Robex Resources Inc. published this content on November 14, 2025, and is solely responsible for the information contained herein. Distributed via Public Technologies (PUBT), unedited and unaltered, on November 14, 2025 at 04:25 UTC.
















