Exhibit 99.1

S-K 1300 Technical Report Summary Initial Assessment of the Ruby Hill Project, Eureka County NV i-80 Gold Corp. Prepared by: FORTE DYNAMICS, INC 120 Commerce Drive, Units 3 & 4 Fort Collins, Colorado 80524 Prepared for: i-80 Gold Corp. 5190 Neil Road, Suite 460 Reno, Nevada 89502 Others: Practical Mining LLC TR Raponi Consulting Ltd. Effective Date: December 31, 2024 Issue Date: March 29, 2025 QP Firms: Practical Mining LLC TR Raponi Consulting Ltd. Forte Dynamics, Inc.

		March 29, 2025

 

VERSION CONTROL

 

Rev. No		Date		Status		Prepared By		Checked By		Approved By
REV A		3/19/2025		DRAFT		K. Ollila		J. Heiner		A. Amoroso
REV B		3/25/2025		DRAFT		K. Ollila		J. Heiner		A. Amoroso
REV C		3/29/2025		FINAL		K. Ollila		J. Heiner		A. Amoroso

 

 

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DATE AND SIGNATURE PAGE

S-K 1300 Initial Assessment and Technical Report Summary, Ruby Hill Complex, Eureka County, Nevada

Prepared for: i-80 Gold Corporation

Report Date: March 29, 2025

Prepared by the following Firms:

 

QP Firm		Responsibilities/Contributions		Signature		Date
Practical Mining LLC		1-9, 11.1, 11.2, 12, 13.1, 15.1, 16, 17, 18.1, 19.1, 20-25				March 28, 2025
TR Raponi Consulting Ltd.		1, 10, 14.1, 14.2, 22-24				March 28, 2025
Forte Dynamics, Inc.		1, 2, 11.1, 11.3, 11.4, 12, 13.2, 13.3, 14.3, 15.2, 18.2, 19.2, 21-25				March 28, 2025

 

 

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Table of Contents

 

Date and Signature Page			3
1.  Executive Summary			17
1.1   Introduction			17
1.2   Property Description			19
1.3   Geology and Mineral Deposits			20
1.3.1   Distal Disseminated			20
1.3.2   Carlin Type			20
1.3.3   CRD and Skarn			21
1.4   Metallurgical Testing and Processing			22
1.4.1   Archimedes Underground			22
1.4.2   Mineral Point Open Pit			22
1.5   Mineral Resources			23
1.5.1   Archimedes Underground			23
1.5.2   Archimedes Open Pit			24
1.5.3   Mineral Point Open Pit			25
1.6   Mining, Infrastructure, and Project Schedule			26
1.6.1   Archimedes Underground			26
1.6.2   Archimedes Open Pit			26
1.6.3   Mineral Point Open Pit			26
1.7   Economic Analysis			27
1.7.1   Archimedes Underground			27
1.7.2   Mineral Point Open Pit			28
1.8   Conclusions			30
1.8.1   Archimedes Underground			30
1.8.2   Archimedes Open Pit			31
1.8.3   Mineral Point Open Pit			31
1.9   Recommendations			32
1.9.1   Archimedes Underground			32
1.9.2   Archimedes Open Pit			32
1.9.3   Mineral Point Open Pit			32
1.9.4   Work Programs			34
2.  Introduction			36
2.1   Registrant for Whom the Technical Report Summary was Prepared			36
2.2   Terms of Reference and Purpose of this Technical Report			36
2.3   Qualified Persons			36
2.4   Details of Personal Inspection by Qualified Persons			37
2.5   Report Version Update			37
2.6   Units of Measure			37
2.7   Coordinate System			38
2.8   Mineral Resource and Mineral Reserve Definitions			39
3.  Property Description			40
3.1   Property Description			40
3.2   Status of Mineral Titles			40
3.3   Royalties			47
3.4   Environmental Liabilities			49
3.5   Permits/Licenses			49

 

 

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4.  Accessibility, Climate, Local Resources, Infrastructure, and Physiography			50
4.1   Accessibility			50
4.2   Climate			50
4.3   Local Resources			50
4.4   Infrastructure			50
4.5   Physiography			50
5.  History			52
5.1   Historic Ownership			52
5.2   Historic Mining			54
5.3   Historic Exploration			55
6.  Geologic Setting, Mineralization and Deposit Types			60
6.1   Regional Geology			60
6.2   Project Geology			62
6.3   Stratigraphy			65
6.3.1   Lower Cambrian			65
6.3.2   Middle Cambrian			65
6.3.3   Upper Cambrian			66
6.3.4   Lower-Middle Ordovician			66
6.3.5   Cretaceous			67
6.3.6   Tertiary/Quaternary			68
6.4   Structure			69
6.4.1   Archimedes Deposit Structure			70
6.4.2   Mineral Point Trend Structure			71
6.4.3   Historic Ruby Hill and FAD Structure			73
6.5   Alteration			74
6.5.1   Archimedes Deposit Alteration			74
6.5.2   Mineral Point Trend Alteration			74
6.5.3   Historic Ruby Hill and FAD Alteration			75
6.6   Mineralization			75
6.6.1   Archimedes Deposit Mineralization			78
6.6.2   Mineral Point Trend Mineralization			79
6.6.3   Historic Ruby Hill and FAD Mineralization			79
6.7   Deposit Types			80
6.7.1   Characteristics of Polymetallic Carbonate Replacement Deposits			80
6.7.2   Characteristics of Skarn Deposits			80
6.7.3   Characteristics of Carlin-Type Gold Deposits			80
6.7.4   Distal-disseminated Mineralization at Ruby Hill			81
7.  Exploration			82
7.1   Geophysical			82
7.1.1   Archimedes Area			82
7.1.2   FAD Area			83
7.2   Drilling			85
7.2.1   Historic Drilling at Ruby Hill			85
7.2.2   Drilling Methods			89
7.2.3   Geological Logging			91
7.2.4   Sample Recovery			91
7.2.5   Collar Surveys			91
7.2.6   Downhole Surveys			91
7.2.7   Metallurgical Drilling			92

 

 

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7.2.8   Sample Length/True Thickness			94
7.2.9   Potential Downhole Contamination			94
7.2.10  Summary and Interpretation of All Relevant Drilling Results			94
7.2.11  i-80 Drilling			94
7.3   Hydrogeology			95
7.3.1   Sampling Methods and Laboratory Determinations			95
7.3.2   Hydrogeology Investigations			95
7.3.3   Hydrogeologic Description			96
7.3.4   Mine Dewatering			101
7.3.5   Dewatering Discharge			101
7.3.6   Groundwater Flow Model			102
7.3.7   Model Results			105
8.  Sample Preparation, Analysis and Security			111
8.1   Sampling Methods			111
8.2   Analytical and Test Laboratories			111
8.3   Density Determinations			111
8.4   Sample Preparation and Analysis			113
8.4.1   Barrick			113
8.4.2   Homestake			114
8.5   Quality Assurance and Quality Control (QA/QC)			115
8.5.1   Barrick QA/QC Program			115
8.6   Historical Databases			121
8.7   Historical Sample Security			121
8.8   Comments on Historic Ruby Hill Data			121
8.9   i-80 Sample Preparation, Laboratory Analysis, Security, and Quality Control Procedures			122
8.9.1   i-80 Sample Preparation Procedures			122
8.10  i-80 Standards and Blanks			123
8.11  i-80 Duplicate Assays			123
8.12  QP Opinion			124
9.  Data Verification			126
9.1   Historical Data Review			126
9.2   Wood Data Verification 2021			126
9.3   Practical Mining Data Verification 2023			126
10.  Mineral Processing and Metallurgical Testing			128
10.1 Archimedes Underground			128
10.1.1  Refractory Testing Programs			128
10.1.2  Deleterious Elements			133
10.1.3  Recovery Estimates			134
10.2 Mineral Point Open Pit			135
10.2.1  Historical Operations			135
10.2.2  Historical Test Work			135
10.2.3  Mineral Point Leach Cycle Times			141
10.2.4  Mineral Point Reagent Consumptions			141
10.2.5  Deleterious Elements			141
10.2.6  Recovery Estimates			142
11.  Mineral Resource Estimates			144
11.1 Introduction			144

 

 

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11.2 Archimedes Underground			145
11.2.1  Grade Shells			146
11.2.2  Density			146
11.2.3  Statistics			148
11.2.4  Grade Capping			152
11.2.5  Block Model			153
11.2.6  Model Validation			153
11.2.7  Resource Classification			159
11.2.8  Factors That May Affect Mineral Resources			159
11.2.9  Reasonable Prospects for Eventual Economic Extraction			159
11.2.10  Archimedes Underground Mineral Resource Statement			159
11.2.11  QP Opinion			161
11.3 Archimedes Open Pit			161
11.3.1  Summary Workflow			161
11.3.2  Exploratory Data Analysis (EDA)			161
11.3.3  Resource Estimation			165
11.3.4  Model Validation			166
11.3.5  Mineral Resource Classification			170
11.3.6  Reasonable Prospects for Eventual Economic Extraction			170
11.3.7  Archimedes Open Pit Mineral Resource Statement			170
11.3.8  QP Opinion			171
11.4 Mineral Point Open Pit			171
11.4.1  Summary Workflow			172
11.4.2  Geological Modeling			172
11.4.3  Exploratory Data Analysis			174
11.4.4  Grade Estimation			177
11.4.5  Resource Model Validation			180
11.4.6  Bulk Density			183
11.4.7  Mineral Resource Classification			183
11.4.8  Reasonable Prospects for Eventual Economic Extraction			184
11.4.9  Mineral Point Open Pit Mineral Resource Statement			185
11.4.10  Factors that may Affect Mineral Resources			185
11.4.11  QP Opinion			186
12.  Mineral Reserve Estimates			187
13.  Mining Methods			188
13.1 Archimedes Underground			188
13.1.1  Mine Development			188
13.1.2  Mining Methods			189
13.1.3  Geotechnical and Ground Support			191
13.1.4  Cemented Rock Fill			200
13.1.5  Staffing and Underground Equipment Requirements			200
13.1.6  Mine Plan			201
13.2 Archimedes Open Pit			206
13.3 Mineral Point Open Pit			206
13.3.1  Initial Pit Limit Evaluations			206
13.3.2  Open Pit Economic Parameters			207
13.3.3  Pit Designs			215
13.3.4  Haul Road Design			227
13.3.5  Economic Evaluation			228
13.3.6  Cutoff Grade			228
13.3.7  Pit Design Inventories			228
13.3.8  Drilling and Blasting			229
13.3.9  Production Schedules			229

 

 

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13.3.10  Mine Fleet			231
13.3.11  Dewatering			231
14.  Recovery Methods			232
14.1 Archimedes Underground			232
14.1.1  Introduction			232
14.1.2  Refractory Mineralization Processing			232
14.2 Lone Tree Pressure Oxidation Facility			234
14.2.1  Lone Tree Mill Historic Processing			234
14.2.2  Lone Tree Facility Block Flow Diagram			235
14.2.3  Key Design Criteria			237
14.2.4  Lone Tree Facility Description			237
14.2.5  Utilities Consumption			241
14.3 Mineral Point Open Pit			243
14.3.1  Summary Process Design Criteria			243
14.3.2  Process Descriptions			245
14.3.3  Process Water			247
14.3.4  Process Flowsheet			247
15.  Infrastructure			249
15.1 Archimedes Underground			249
15.1.1  Operations Dewatering			249
15.1.2  Operations Monitoring Wells and VWPs			249
15.1.3  Operations RIBs			249
15.1.4  Operations Water Supply			249
15.1.5  Electrical Power			249
15.1.6  Underground Mine Facilities			249
15.1.7  Backfill			250
15.2 Mineral Point Open Pit			256
15.2.1  Site Layout			256
15.2.2  Existing Infrastructure			258
15.2.3  Planned Infrastructure			259
15.2.4  Operations Dewatering			264
15.2.5  Operations Monitoring			267
15.2.6  Water Supply			267
16.  Market Studies and Contracts			268
16.1 Precious Metal Markets			268
16.2 Contracts			269
16.2.1  Financing Agreements			269
16.3 Refractory Mineralized Material Sale Agreement			271
16.4 Other Contracts			271
17.  Environmental Studies, Permitting and Social or Community Impact			272
17.1 Closure and Reclamation Requirements			272
17.2 Social or Community Impacts			272
17.3 Permits			273
17.4 Water Use Permits			274
17.5 QP Opinion			274
18.  Capital and Operating Costs			275
18.1 Archimedes Underground			275

 

 

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18.1.1  Capital Costs			275
18.1.2  Operating Costs			275
18.1.3  Cutoff Grade			276
18.2 Mineral Point Open Pit			277
18.2.1  Capital Cost Estimate			277
18.2.2  Operating Cost Estimate			279
19.  Economic Analysis			281
19.1 Archimedes Underground			281
19.1.1  Taxes			281
19.1.2  Cash Flow			281
19.1.3  Sensitivity			291
19.2 Mineral Point Open Pit			293
19.2.1  Principal Assumptions			293
19.2.2  Operating Cost			293
19.2.3  Capital Costs			293
19.2.4  Cost Summary			294
19.2.5  Economic Model			294
19.2.6  Economic Analysis Without Inferred Resources			301
20.  Adjacent Properties			302
21.  Other Relevant Data and Information			303
22.  Interpretation and Conclusions			304
22.1 Conclusions			304
22.1.1  Archimedes Underground			304
22.1.2  Archimedes Open Pit			305
22.1.3  Mineral Point Open Pit			305
22.2 Risks and Opportunities			305
23.  Recommendations			309
23.1 Archimedes Underground			309
23.1.1  Metallurgical Testing			309
23.1.2  Permitting and Mine Development			309
23.1.3  Resource Conversion and Exploration Drilling			309
23.1.4  Dewatering			309
23.2 Archimedes Open Pit			309
23.2.1  Mineral Resources			309
23.3 Mineral Point Open Pit			309
23.3.1  Mineral Resources			309
23.3.2  Mining and Infrastructure			310
23.3.3  Metallurgical Testing			310
23.4 Work Program			311
23.4.1  Archimedes Underground			311
23.4.2  Archimedes Open Pit			312
23.4.3  Mineral Point Open Pit			312
24.  References			313
25.  Reliance on Information Provided by the Registrant			320

 

 

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Figures

 

Figure 1-1: Ruby Hill Complex Overview			18
Figure 3-1: Ruby Hill Complex Location Map			40
Figure 3-2: Ruby Hill Complex Land Position			41
Figure 3-3: Ruby Hill Royalty Map			48
Figure 5-1: Geophysical Surveys in the Ruby Hill Project Area			57
Figure 5-2: Rock Samples with Gold Grade (opt) within the Ruby Hill Claim Block			58
Figure 5-3: Soil Samples with Gold Grade (opt) within the Ruby Hill Claim Block			59
Figure 6-1: Regional Geologic Map			61
Figure 6-2: Ruby Hill Project Geology and Deposit Locations			64
Figure 6-3: Ruby Hill Stratigraphic Column			68
Figure 6-4: Geology of East Archimedes, West Archimedes and Archimedes Underground Including 426, and Ruby Deeps Zones			71
Figure 6-5: Mineral Point Trend Geology			72
Figure 6-6: Historic Ruby Hill and FAD Deposit Geology			73
Figure 6-7: Plan View of Ruby Deeps, 426, 007, 008, Blackjack, and Hilltop Zones			76
Figure 6-8: Plan View of Mineral Point Trend and Archimedes Deposits			77
Figure 6-9: Fence Section of Mineral Point Trend and Archimedes Deposits			78
Figure 7-1: Exploration Targets at Ruby Hill			84
Figure 7-2: Drill Hole Collar Locations			86
Figure 7-3: Distribution of Drill Types Included in the 2021 Ruby Hill Project Mineral Resource Estimate			87
Figure 7-4: Plan View of Drilling by Campaign			88
Figure 7-5: Fence Section of Drilling by Campaign (Looking North)			89
Figure 7-6: Diamond Valley Hydrographic Basin and Ruby Hill Mine Permit Area			98
Figure 7-7: Surface Geology and Pre-Mining Groundwater Level Contours			99
Figure 7-8: Dewatering Well and Groundwater Monitoring Locations			102
Figure 7-9: Property Overview showing Plan Operations Boundary, Existing Mine Operations Boundary, and Existing Archimedes Pit with Planned UGWs for the 426 and Blackjack Deposits			103
Figure 7-10: Schematic Section through the Archimedes Pit Area			104
Figure 7-11: Ground Water Flow Model Boundary			106
Figure 7-12: Ground Water Flow Model Grid			107
Figure 7-13: Mine-Area Hydrogeologic Zones and Flow Barriers, Layer 2			108
Figure 7-14: Projected Changes in Groundwater Level, End of Mining			109
Figure 8-1: Control Chart for Standard OREAS 54PA			116
Figure 8-2: ALS Global (Chemex) Pulps Checked at Inspectorate			118
Figure 8-3: Mean Versus Half Relative Difference for Field Duplicates			119
Figure 8-4: Scatter Plot of all Lab Duplicates			120
Figure 8-5: Mean Versus Half Relative Difference for Pulp Duplicates			120
Figure 8-6: i-80 Lab Duplicates			124
Figure 8-7: i-80 Prep Duplicates			125
Figure 10-1: 2024 FLSmidth Program Preg-Robbing as a Function of Organic Carbon Concentration			131
Figure 11-1: Block Model Extents			145
Figure 11-2: Underound Model Extents and Drill Hole Traces			146
Figure 11-3: Density Box and Whisker Plot by Lithology Formation			147
Figure 11-4: 426 0.1 Au opt Box and Whisker Plots			148
Figure 11-5: Ruby Deeps 0.1 Au opt Box and Whisker Plots			149
Figure 11-6: 0.002 Au opt Box and Whisker Plots			151

 

 

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Figure 11-7: Gold Cumulative Frequency			152
Figure 11-8: Silver Grade Shells Cumulative Frequency			152
Figure 11-9: 426 Deposit Comparison of Composite and Block Grades			155
Figure 11-10: Ruby Deeps Deposit Comparison of Composite and Block Grades 120450N			156
Figure 11-11: Drift Analysis Gold			157
Figure 11-12: Drift Analysis Silver			158
Figure 11-13: Graphical Statistical Comparison of Rock Units			162
Figure 11-14: Statistics for Key Geological Units			163
Figure 11-15: Composite Study Results			164
Figure 11-16: Gold and Silver Composite Samples within the Indicator Shell			165
Figure 11-17: Example Gold Variogram			165
Figure 11-18: Cross Section of Estimated Block Model and Composites			167
Figure 11-19: Example Swath Plots			168
Figure 11-20: Comparison of Cumulative Frequency			169
Figure 11-21: Fence Section Looking North Showing Main Faults and Stratigraphic Units for the Ruby Hill Project			173
Figure 11-22: Example Cross Section Showing Modeled Sulfide Domain and Redox Codes in the Drillhole Database			174
Figure 11-23: Gold and Silver Raw Assay Sample Grade Histograms and Probability Plots			175
Figure 11-24: Example Cross Section of the Mineral Point Trend Showing Raw Assays (Right of Trace) and Downhole 10 ft. Composites (Left Trace) with the Optimized Pit Shell			176
Figure 11-25: Box and Whisker Plot for Assay Sample Grades and 10 ft. Composites for Gold and Silver			177
Figure 11-26: Indicator Threshold Selection – CV of Gold and Silver Assay Composite Grades			178
Figure 11-27: Au Estimation – Implementation of a Soft Boundary Between LG and HG Composites			179
Figure 11-28: Area of Au High-Grade Blow-out and Eureka Corp Underground Drilling			180
Figure 11-29: Estimated Block Grades and 10 Foot Composite Grades for Gold - Section 121200 N Looking N			181
Figure 11-30: Swath Plots – Gold – Indicated Blocks			182
Figure 11-31: Bulk Density Values by Lithology			183
Figure 11-32: Cross Section Showing the Mineral Point Resource, Resource Pit Shell, and Topo			184
Figure 13-1: Archimedes Underground Isometric View Showing Portals, Main Ramp and Ventilation Development			188
Figure 13-2: Stope Mining Sequence Part A			190
Figure 13-3: Stope Mining Sequence Part B			191
Figure 13-4: RQD Logged Drill Holes (426 - Turquoise, Ruby Deeps - Gold)			192
Figure 13-5: Cross Section 119625N Showing RQD Values (426 - Turquoise, 426 Fault - Gray, Ruby Deeps - Gold, Holly Fault - Red)			193
Figure 13-6: RQD Box and Whisker Plot			194
Figure 13-7: Q-system Support Recommendations			196
Figure 13-8: Q Logged Drill Holes (426 - Blue, Ruby Deeps - Gold)			197
Figure 13-9: Cross Section 119625N Showing Q Values (426 - Blue, 426 Fault - Gray, Ruby Deeps - Gold, Holly Fault - Red)			198
Figure 13-10: Q Value Box and Whisker Plot			199
Figure 13-11: Permitting Development and Initial Production Schedule			202
Figure 13-12: LG Shells by Revenue Factor			209
Figure 13-13: Percentage of Profit, Processed Material, and Recoverable Gold by LG Shell			211
Figure 13-14: Plan View of LG Pit Shells and Cross Section Locations			212

 

 

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Figure 13-15: Pit Optimization Looking West (Section A’ – A)			213
Figure 13-16: Pit Optimization Looking North (Section B’ – B)			213
Figure 13-17: Pit Optimization Looking North (Section C’ – C)			214
Figure 13-18: Pit Optimization Looking North (Section D’ – D)			214
Figure 13-19: Pit Optimization Looking North (Section E’ – E)			215
Figure 13-20: Pit Phasing and Section Line			216
Figure 13-21: Cross Section F’ to F of Pit Phasing			217
Figure 13-22: Phase 1 Design			218
Figure 13-23: Phase 2 Design			219
Figure 13-24: Phase 3 Design			220
Figure 13-25: Phase 4 Design			221
Figure 13-26: Phase 5 Design (First Phase of Heap Leach Relocation)			222
Figure 13-27: Phase 6 Design (Second Phase of Heap Leach Relocation)			223
Figure 13-28: Phase 7 Design			224
Figure 13-29: Phase 8 Design			225
Figure 13-30: Phase 9 Design			226
Figure 13-31: Final Pit and Estimated Block Model in Orthogonal View Looking Northwest			227
Figure 13-32: LOM Annual Production Schedule			230
Figure 14-1: Third Party POX Facility Simplified Flowsheet			233
Figure 14-2: Loan Tree Block Flow Diagram			236
Figure 14-3: Mineral Point Process Flowsheet			248
Figure 15-1: Portal Surface Facilities Conceptual Layout			250
Figure 15-2: Site Layout Map			257
Figure 15-3: Existing Infrastructure			258
Figure 15-4: Hydrologic Blocks of Mineral Point			265
Figure 16-1: Historical Monthly Average Gold and Silver Prices and 36 Month Trailing Average			268
Figure 19-1: Mineralization Mined and Processed with Inferred			286
Figure 19-2: Gold Production and Unit Costs with Inferred			286
Figure 19-3: Mineralization Mined and Processed without Inferred			287
Figure 19-4: Gold Production and Unit Costs without Inferred			287
Figure 19-5: Cash Flow Waterfall Chart with Inferred			289
Figure 19-6: NPV 5% Sensitivity with Inferred			291
Figure 19-7: NPV 8% Sensitivity with Inferred			291
Figure 19-8: IRR Sensitivity with Inferred			292
Figure 19-9: Profitability Index Sensitivity with Inferred			292
Figure 19-10: Pre-Tax LOM Annual Cash Flow			295
Figure 19-11: After-Tax LOM Annual Cash Flow			296
Figure 19-12: Pre-Tax Sensitivity NPV @5%			298
Figure 19-13: Pre-Tax Sensitivity IRR			298
Figure 19-14: After-Tax Sensitivity NPV @5%			299
Figure 19-15: After-Tax Sensitivity IRR			299

 

 

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Tables

 

Table 1-1: Summary of Archimedes Underground Mineral Resources at the End of the Fiscal Year Ended December 31, 2024			23
Table 1-2: Summary of Archimedes Open Pit Mineral Resources at the End of the Fiscal Year Ended December 31, 2024			24
Table 1-3: Summary of Mineral Point Open Pit Mineral Resources at the End of the Fiscal Year Ended December 31, 2024			25
Table 1-4: Capital and Operating Cost Summary			27
Table 1-5: Financial Statistics			28
Table 1-6: Unit and Total Operating Costs With and Without Inferred Resources			29
Table 1-7: After-Tax NPV Comparison of With and Without Inferred Resources			30
Table 1-8: Archimedes Underground Work Program			34
Table 1-9: Mineral Point Work Program			35
Table 2-1: Personal Inspections by Qualified Persons			37
Table 2-2: Units and Abbreviations			38
Table 3-1: Ruby Hill Project Owned Patented Claims			42
Table 3-2: Ruby Hill Project Owned Unpatented Claims			43
Table 3-3: Ruby Hill Project Leased Unpatented Claims			44
Table 3-4: Golden Hill FAD Property Owned Patented Claims			44
Table 3-5: Golden Hill FAD Property Leased Patented Claims			45
Table 3-6: Golden Hill FAD Property Owned Unpatented Claims			46
Table 3-7: Golden Hill FAD Property Leased Unpatented Claims			46
Table 3-8: Ruby Hill Complex Property Holding Costs			47
Table 3-9: Ruby Hill Royalties			47
Table 3-10: Golden Hill Royalties			47
Table 5-1: Historic Regional Ownership and Activities			52
Table 5-2: Production History Summary			55
Table 5-3: Historic Exploration			56
Table 6-1: Major Structural Features and Orientations within the Property Area			69
Table 7-1: Drilling Statistics for Drillholes Included in the 2021 Ruby Hill Project Mineral Resource Estimate			87
Table 7-2: Distribution of Drilling by Campaign			87
Table 7-3: 2004 Barrick Metallurgical Holes			92
Table 7-4: 2009 Metallurgical Holes			93
Table 7-5: 2010 and 2011 Metallurgical Holes			93
Table 7-6: 2011 Metallurgical Holes			93
Table 7-7: Summary of Hydrogeological Surveys Since 2004 (Wood 2021)			96
Table 8-1: Assay, Density and Metallurgical Laboratories			112
Table 8-2: Barrick Rock Type Density Values			113
Table 8-3: ALS Global Gold Analytical Parameters			114
Table 8-4: Count and Description of QA/QC Samples by Year			116
Table 8-5: SRM Performance			117
Table 8-6: Selected i-80 Blank and Standard Reference Results			123
Table 9-1: Drill Holes in 426 and Ruby Deeps Zones			127
Table 9-2: Drillhole Data Fields Reviewed			127
Table 10-1: Ruby Hill Project Refractory Testing Programs			128
Table 10-2: January 2008 426 Zone Barrick Technology Centre Test Results Summary			129

 

 

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Table 10-3: November 2011 426 Zone Barrick Technology Centre Test Results Summary			130
Table 10-4: 2024 FLSmidth Program Assays Summary			130
Table 10-5: FLSmidth Program BTAC Conditions Summary			132
Table 10-6: FLSmidth Program BTAC and Roasting CIL Recovery Summary			132
Table 10-7: November 2011 426 Zone Barrick Technology Centre Refractory Sample Assays Summary			134
Table 10-8: Ruby Hill (Archimedes) Summary of Estimated Gold Recoveries			134
Table 10-9: Ruby Hill Project Historical Metallurgical Testing Programs			135
Table 10-10: June 2004 KCA Archimedes Column Test Results Summary			136
Table 10-11: May 2005 KCA Archimedes Column Test Results Summary			136
Table 10-12: January 2009 426 Zone KCA Column Leach Test Results Summary			137
Table 10-13: November 2011 426 Zone KCA Column Leach Test Results Summary			137
Table 10-14: February 2011 Mineral Point Deposit KCA Bottle Rolls Test Results Summary			138
Table 10-15: February 2011 Mineral Point Deposit KCA Column Leach Test Results Summary			138
Table 10-16: July 2012 Mineral Point Deposit KCA Bottle Rolls Test Results Summary			139
Table 10-17: July 2012 Mineral Point Deposit KCA Column Leach Test Results Summary			139
Table 10-18: February 2014 Mineral Point Deposit KCA Bottle Rolls Test Results Summary			140
Table 10-19: February 2014 Mineral Point Deposit KCA Column Leach Test Results Summary			141
Table 10-20: Summary of Column Leach Test Results			142
Table 10-21: Mineral Point Summary of Estimated Gold and Silver Recoveries			143
Table 11-1: Univariate Density Statistics by Lithology Formation (tonnes/m3)			147
Table 11-2: Gold Univariate Statistics for 426 0.1 Au opt Composites			148
Table 11-3: Silver Univariate Statistics for 426 0.1 Au opt Composites			149
Table 11-4: Gold Univariate Statistics for Ruby Deeps 0.01 Au opt Composites			150
Table 11-5: Silver Univariate Statistics for Ruby Deeps 0.01 Au opt Composites			150
Table 11-6: Gold Univariate Statistics for 0.002 Au opt Composites			151
Table 11-7: Silver Univariate Statistics for 0.002 Au opt Composites			151
Table 11-8: Gold and Silver Grade Caps			153
Table 11-9: Estimation Search Distances and Sample Requirements			153
Table 11-10: Ellipsoid Search Parameters for each Grade Shell			153
Table 11-11: Comparison of Composite and Block Model Statistics			154
Table 11-12: Mineral Resource Classification Scheme			159
Table 11-13: Summary of Archimedes Underground Mineral Resources at the End of the Fiscal Year Ended December 31, 2024			160
Table 11-14: Summary Sample Statistics - Archimedes			162
Table 11-15: Variogram for 0.05 Au ppm Indicator			164
Table 11-16: Variograms for Au and Ag			166
Table 11-17: Gold and Silver Search Parameters			166
Table 11-18: Resource Classification by Sample Density			170
Table 11-19: Summary of Archimedes Open Pit Mineral Resources at the End of the Fiscal Year Ended December 31, 2024			171
Table 11-20: Estimation Parameters			179
Table 11-21: Global Bias Check within Indicated Resources			181
Table 11-22: Parameters for Mineral Resource Pit Shell Construction			184
Table 11-23: Summary of Mineral Point Open Pit Mineral Resources at the End of the Fiscal Year Ended December 31, 2024			185
Table 13-1: Guidelines for the Selection of Primary Support for 20-foot to 40-foot Tunnels in Rock			192
Table 13-2: RQD Univariate Statistics by Grade Shell			194

 

 

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Table 13-3: Q Value Univariate Statistics by Grade Shell			199
Table 13-4: Personnel Requirements			200
Table 13-5: Equipment Requirements			201
Table 13-6: i-80 Support Equipment			201
Table 13-7: Ruby Hill Development Schedule			202
Table 13-8: Archimedes Production Mining Plan (Includes Inferred Mineral Resource)			203
Table 13-9: Mine Production Rates by Excavation Type			203
Table 13-10: Ruby Hill Processing Plan (Includes Inferred Mineral Resource)			204
Table 13-11: Ruby Hill Processing Plan (Without Inferred Mineral Resource)			205
Table 13-12: Pit Slope by Lithology Unit			207
Table 13-13: Pit Optimization Parameters			207
Table 13-14: Profit Factor for Optimization Results			210
Table 13-15: Pit Design Parameters			215
Table 13-16: Design Metal Prices, Costs, and Recoveries			228
Table 13-17: In-Pit Mineral Resources by Pit Phase			229
Table 13-18: LOM Production Schedule			230
Table 13-19: Mining Equipment List			231
Table 14-1: Summary of Key Process Statistics			237
Table 14-2: Lone Tree Facility Water Consumption by Type			242
Table 14-3: Lone Tree Facility Energy Usage by Area			242
Table 14-4: Mineral Point Design Criteria			243
Table 15-1: Ruby Hill Active Dewatering Wells (LRE 2025)			251
Table 15-2: Summary of Locations, Construction Information, and Water Levels for Dewatering Wells, VWPs, Monitoring Wells, and Piezometers			252
Table 15-3: Existing Infrastructure Plans			259
Table 15-4: Heap Leach Pad Phases			260
Table 15-5: WRSA Parameters			261
Table 15-6: Ruby Hill Pumping Wells			266
Table 17-1: Ruby Hill Project Significant Permits			273
Table 18-1: Mine Development Unit Costs			275
Table 18-2: Project Capital Costs ($M)			275
Table 18-3: Underground Mine Operating Costs			276
Table 18-4: Resource Cutoff Grades by Process			276
Table 18-5: Mineral Point Project Capital Cost Summary			277
Table 18-6: Mineral Point Mining Equipment LOM CAPEX			278
Table 18-7: Mineral Point Process Infrastructure LOM CAPEX			278
Table 18-8: Mineral Point Pre-Production and Facilities LOM CAPEX			279
Table 18-9: Mineral Point Owner’s Costs LOM CAPEX			279
Table 18-10: Mineral Point LOM Operating Cost Summary			280
Table 18-11: Mineral Point Processing Costs			280
Table 19-1: Income Statement with Inferred			282
Table 19-2: Cash Flow Statement with Inferred			283
Table 19-3: Income Statement without Inferred			284
Table 19-4: Cash Flow Statement without Inferred			285
Table 19-5: Capital and Operating Cost Summary With Inferred			288
Table 19-6: Capital and Operating Cost Summary Without Inferred			288
Table 19-7: Financial Statistics			290
Table 19-8: Economic Model Parameters			293

 

 

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Table 19-9: Cost Summary			294
Table 19-10: Pre-Tax NPV Summary			295
Table 19-11: After-Tax NPV Summary			295
Table 19-12: Sensitivity Summary			297
Table 19-13: Gold and Silver Price Sensitivity After-Tax Analysis			300
Table 19-14: Economic Model Parameters Comparison of With and Without Inferred Resources			301
Table 19-15: After-Tax NPV Comparison of With and Without Inferred Resources			301
Table 22-1: Risks and Uncertainties			307
Table 22-2: Opportunities			308
Table 23-1: Archimedes Underground Work Program			311
Table 23-2: Mineral Point Work Program			312

Appendices

Appendix A – Site Visit Report

Appendix B – Mineral Point Open Pit Economic Model with Inferred Resources

 

 

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1.	EXECUTIVE SUMMARY

 

1.1	Introduction

This Technical Report Summary (“TRS”) dated the 29th day of March, 2025 with an effective date of December 31, 2024 provides an updated statement of Mineral Resources for Ruby Hill Mining Company LLC’s Ruby Hill Complex. This Technical Report Summary provides an Initial Assessment (“IA”) for the Archimedes Underground, Archimedes Open Pit, and Mineral Point Open Pit Resource areas at Ruby Hill.

The mining contemplated for each of these areas is independent of the other and there is no interaction between them. Exploitation of one area does not preclude exploitation of the other. This report considers each to be a stand-alone operation, and there has not been any shared benefit assigned to operating or capital costs.

The Ruby Hill property contains several historical mines, current resources, and exploration targets (Figure 1-1). The property is endowed with multiple types of mineralization, including Carlin-style gold, distal disseminated silver-gold, carbonate replacement deposits (CRD), and skarn base metals. i-80 is currently focused on precious metal deposits. The resources considered in this report include the Archimedes Underground Carlin-style gold deposit and the Mineral Point distal disseminated silver-gold deposit.

 

 

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Figure 1-1: Ruby Hill Complex Overview

(Source: i-80 Gold, 2023)

Cautionary Note:

The financial analysis contains certain information that may constitute “forward-looking information” under applicable United States securities legislation. Forward-looking information includes, but is not limited to, statements regarding

 

 

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the Company’s achievement of the full-year projections for ounce production, production costs, AISC costs per ounce, cash cost per ounce and realized gold/silver price per ounce, the Company’s ability to meet annual operations estimates, and statements about strategic plans, including future operations, future work programs, capital expenditures, discovery and production of minerals, price of gold and currency exchange rates, timing of geological reports and corporate and technical objectives. Forward-looking information is necessarily based upon a number of assumptions that, while considered reasonable, are subject to known and unknown risks, uncertainties, and other factors which may cause the actual results and future events to differ materially from those expressed or implied by such forward looking information, including the risks inherent to the mining industry, adverse economic and market developments and the risks identified in Premier’s annual information form under the heading “Risk Factors”. There can be no assurance that such information will prove to be accurate, as actual results and future events could differ materially from those anticipated in such information. Accordingly, readers should not place undue reliance on forward-looking information. All forward-looking information contained in this Presentation is given as of the date hereof and is based upon the opinions and estimates of management and information available to management as at the date hereof. Premier disclaims any intention or obligation to update or revise any forward-looking information, whether as a result of new information, future events or otherwise, except as required by law.

 

1.2	Property Description

The Ruby Hill property is located in the historic Eureka mining district. It lies west of the town of Eureka in Eureka County, central Nevada. It is a large property containing multiple deposit types and several past-producing mines, and as such it has a long history of prior ownership and production. The property takes its name from the most significant historical mine, the Ruby Hill mine, named for the hill it lies beneath roughly 1.2 miles southwest of Eureka. Historic mining generally exploited silver and base metal mineralization with the majority of production coming from the Ruby Hill mine from 1873-1916. Sporadic exploration and production from 1916 through 1959 included discovery and mining of the TL, Holly and Helen deposits roughly 1.2 miles north of Ruby Hill as well as further attempts to re-access the Ruby Hill mine and a largely as-yet unexploited deposit interpreted as a lower offset of the Ruby Hill deposit known as FAD. The FAD and Locan shafts were sunk to target depths but were plagued by unmanageable water inflows when crosscut mining intersected water bearing structures.

Modern mining began in 1992 with the discovery of the Archimedes Carlin-style gold deposit roughly 1.5 miles NNE of Ruby Hill and one mile NNW of Eureka. Archimedes has been mined using open pit methods from 1997-2002, 2007-2013, and 2020-2021. A pit wall failure in 2013 made continued large scale open pit mining unfeasible due to the economic environment at that time, but continued exploration delineated resources exploitable using underground mining methods. These resources are collectively called Archimedes Underground.

The mineral deposits being considered for economic extraction in this TR are the Archimedes Underground and the Mineral Point deposits.

The Mineral Point deposit was delineated by previous owners between 1992 and 2015 but has not been mined with the exception of limited areas at the southern end of the deposit exploited by the historic TL, Holly and Helen underground mines.

The property is located on owned fee land, owned and leased patented mining claims, and owned and leased unpatented mining claims. i-80 Gold purchased the northern portion of the Ruby Hill property, containing the Archimedes and Mineral Point deposits and small historic underground mines including TL, Holly and Helen from Waterton Global in 2021. The southern portion of the property, including the historic Ruby Hill mine and FAD deposit, was acquired by i-80 through a merger with Golden Hill Mining Corporation in 2022. The Ruby Hill complex comprises 10,608 acres from the Ruby Hill purchase and 3,229 acres from the Golden Hill Merger. i-80 differentiates the property for managerial/administrative purposes, referring to

 

 

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the northern portion as Ruby Hill and the southern portion as Golden Hill. Collectively they are known as the Ruby Hill Project or the Ruby Hill Complex.

 

1.3	Geology and Mineral Deposits

The Ruby Hill Project is located along the southeastern end of the Battle Mountain/Eureka gold trend. The Eureka gold mining district exposes a nearly continuous sequence of Cambrian and Ordovician sedimentary rocks approximately 10,000’ thick consisting primarily of carbonate units which are favorable for mineralization with subordinate shale and quartz sandstone.

Mineralization at Ruby Hill is characterized by intrusion-related distal-disseminated silver-gold, carbonate replacement base metal deposits, and skarn deposits that have been overprinted by younger Carlin-type gold mineralization. The main precious metal mineralization at Ruby Hill occurs in favorable lithostratigraphic units bound by high angle structures that are interpreted to have been conduits for hydrothermal fluids responsible for gold and silver mineralization. The earlier carbonate replacement base metal mineralization occurs in metamorphosed and skarn-altered limestone units proximal to Cretaceous intrusions.

 

1.3.1

Distal Disseminated

The Mineral Point deposit consists of gold and silver mineralization hosted by the Cambrian Hamburg dolomite in the nose of a broad anticline that plunges gently to the north-northwest and is bound to the east by the Holly Fault and to the west by the Spring Valley Fault. The Mineral Point Trend is 10,000 ft long, 2,400 ft wide and up to 500 ft thick. The top of the Mineral Point Trend is near surface at its south end and 500 ft below surface at its north end. The majority of the mineralization in the Mineral Point deposit is oxidized and has a high ratio of cyanide soluble to fire assay total gold. This deposit has not been mined and is the largest (and lowest grade) precious metal mineral resource in the Ruby Hill Project.

 

1.3.2

Carlin Type

The Archimedes deposit was discovered by Homestake Mining Company in 1992. The upper portions, called West and East Archimedes, were mined as the Archimedes open pit by Homestake followed by Barrick Gold Corporation from 1998 through 2015, and to a lesser extent by Ruby Hill Mining Company, LLC in 2020 and 2021. The Archimedes Underground remains unmined.

The West Archimedes deposit is hosted in the Ordovician Upper Goodwin limestone unit and is bound to the west by the Holly Fault. The zone strikes north-west and dips shallowly to the north-east. The deposit measures 2,000 ft along strike and 740 ft down dip and is up to 300 ft thick. The majority of West Archimedes was mined as an open pit before mining at East Archimedes. The mineralization in the West Archimedes deposit is oxidized and has a high ratio of cyanide soluble to fire assay total gold.

The East Archimedes Zone occurs east of the Graveyard Fault and proximal to the Graveyard Stock. Mineralization extends eastward from the West Archimedes Zone in the Upper Goodwin Formation and extends downward in the Lower Laminated and Lower Goodwin units along the contact with the Graveyard Stock. Silver and base metal grades are elevated in the East Archimedes zone in comparison with the other zones in the Ruby Hill Project in an envelope around the Blackjack zone replacement-style zinc mineralization described below. Mineralization in East Archimedes is roughly 1,200 ft wide and 1,200 ft long in plan and extends from surface where it is well defined by shallow drilling to several mineralized intersections over 1,800 ft below surface. The upper portion of the East Archimedes deposit, above an elevation of approximately 5,000 ft, is oxidized and transitional oxide-sulfide mineralization with a high ratio of cyanide soluble to total fire assay gold. The upper portion of the East Archimedes zone has been mined.

 

 

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The Archimedes Underground lies below, and extends north of, the Archimedes pit. It includes multiple zones of Carlin-type mineralization characterized by mineralization controlling faults and differing lithologic units with increasing depth. Mineralization is variably oxidized and refractory.

The 426 zone occurs in the Lower Laminated unit of the Goodwin Formation and the upper part of the underlying basal Goodwin unit of the Goodwin Formation in the nose of a fold. The mineralized zone forms a rod-shaped body plunging shallowly to the northeast that is 1,400 ft long, 200 ft wide and 200 ft thick. The top of the zone is approximately 1,000’ below surface, but it is 500’ below the bottom of the current East Archimedes pit bottom. The majority of the higher-grade mineralization occurring in the Goodwin Formation Lower Laminated unit is sulfide-style mineralization with a low ratio of cyanide soluble to total fire assay gold but the lower portion of the zone that is hosted in the basal Goodwin Unit has a moderate cyanide soluble to total fire assay gold mineralization.

The Ruby Deeps zone is a north-south striking, shallowly east dipping zone of mineralization hosted in the Windfall Formation and Dunderberg Shale in proximity to bodies of Bullwhacker Sill intrusive bound by the Graveyard Fault to the east and the Holly Fault to the west. The zone is 2,400 ft long 500 ft wide and 600 ft thick. The top of the zone is 1,600 ft below surface and 1,000 ft below the bottom of the West Archimedes pit. Within the zone there are several tabular horizons of higher-grade mineralization that are 40 ft to 100 ft thick.

The 007 Zone is an exploration target controlled by the NE trending NS Fault. Higher-grade oxide Au mineralization within the fault zone has been intersected by two holes, Barrick’s RC hole P7, 55’ @ 0.291 Au opt and i-80’s core hole iRH22-18A, 43.9’ @ 0.276 Au opt. Three more i-80 holes west of the fault zone intersect mineralization extending west into the Bullwhacker member. The zone is untested to the north and south, currently projecting about 400 ft along strike, 100 ft along dip, and ranges from 10 ft thick where stratigraphically controlled to over 40 ft thick within the NS fault zone.

The 008 Zone is an early exploration stage target. It is stratigraphically controlled, lying near the top of the Windfall Formation in the hinge of an anticline bracketed by the 426 and NS faults. The anticline appears to have formed above an intrusive lens emplaced within the upper member of the Windfall Formation, stratigraphically higher than typical Cretaceous sill material, which typically intruded along the lower contact of the Windfall Fm. The 008 Zone is not well defined but currently is about 350 ft long by 200 ft wide by 15 ft thick.

 

1.3.3

CRD and Skarn

Skarn and CRD mineralization are known to occur on the property but are not being considered for extraction in the current analysis.

Polymetallic (Au-Ag-Pb-Zn) skarn and carbonate replacement deposit (CRD) mineralization is lithologically and structurally controlled. Skarn occurs at Blackjack and the Hilltop Fault-Graveyard Flats stock intersection, primarily within the carbonate-rich Ordovician and mid to upper Cambrian formations adjacent to the Graveyard Flats stock. Minor skarn and CRD mineralization occur within the Cretaceous intrusive units.

Blackjack is a pod of zinc skarn mineralization hosted by the Lower Goodwin Unit proximal to the Graveyard Flats stock within the East Archimedes Zone below the Archimedes pit. It has elevated lead, copper and silver due to CRD overprinting. The base metal-rich CRD and skarn mineralization has been overprinted by later Carlin-style gold mineralization resulting in locally higher-grade gold zones. It is approximately 750 ft wide, 750 ft long and 900 ft high. The Hilltop Fault-Graveyard Flats stock intersection is an exploration stage target and has not been well defined.

 

 

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CRD mineralization tends to occur in the carbonate-rich formations along WNW trending faults. Examples include the historic Ruby Hill mine, the FAD deposit and the Hilltop exploration target.

 

1.4	Metallurgical Testing and Processing

 

1.4.1

Archimedes Underground

The Ruby Hill project encompasses several deposits and mineralization types hosting both precious and base metals. Historical production dates to 1998, primarily under Homestake Mining and Barrick Gold, with intermittent operations up to the current date.

Assumptions are based on historic and current metallurgical performance and the test work reports for oxide gold heap leaching, benchmarks, and the test work reports for zinc sulfide flotation. No detailed process design or production planning has been undertaken at this stage of the Project.

Historically, there have been three destinations for treatment of mineralization from the Ruby Hill Mine: (i) run of mine (ROM) and crushed mineralization to a heap leach pad, (ii) crushing and tank leaching with agglomerated tailings routed to the heap leach pad, and (iii) higher-grade sulfide mineralization (DSO) routed to Nevada Gold Mines Goldstrike Operation for autoclave processing.

For the Archimedes Underground, production with be processed at a third party destination capable of processing refractory ore until such time that i-80 has refurbished the Lone Tree Autoclave facility. The third party destination is an autoclave circuit capable of processing 4 - 5 million tons per year and consists of primary crushing, two parallel semi-autogenous grinding (SAG) Mill-Ball Mill grinding circuits with pebble crushing, five parallel autoclaves capable of acid pressure oxidation (POX) and three of which are capable of alkaline POX, two parallel calcium thiosulphate (CaTS) leaching circuits with resin-in-leach (RIL), electrowinning for gold recovery, and a refinery producing doré bullion from both autoclave and roaster circuits.

The Lone Tree Autoclave Facility is located immediately adjacent to i-80, approximately 12 miles west of Battle Mountain, 50 miles east of Winnemucca, and 120 miles west of Elko. The Lone Tree processing facilities were shut-down at the end of 2007. Since that time, the mills have been rotated on a regular basis to lubricate the bearings. In general, the facility is still in place with most of the equipment sitting idle. i-80 Gold Corp’s objective is to refurbish and restart the POX circuit and associated unit operations, including the existing oxygen plant, as it was operating before the shut-down, while meeting all new regulatory requirements. The flotation circuit is not being considered for restart. The POX circuit will have capability to operate under either acidic or basic conditions.

 

1.4.2

Mineral Point Open Pit

The Mineral Point project encompasses several deposits and mineralization types hosting both precious and base metals. Historical production dates to 1998, primarily under Homestake Mining and Barrick Gold, with intermittent operations up to the current date.

Generally, previous operating experience as well as the metallurgical test work confirms the amenability of oxide material to heap leaching for precious metals extraction. From 2004 to 2014, seven test work programs were carried out, by Kappes Cassiday Associates (KCA) focusing on column leaching and bottle roll leach testing of the oxide deposits, namely Archimedes, 426 and Mineral Point. Mineral Point estimated recoveries are based on alteration type ranging from 83% to 84.4% gold and 40% to 45.2% silver for oxide mineralization. The proposed process for Mineral Point Open Pit material is a two-stage crush conventional heap leach operations with a Merrill-Crowe processing facility.

 

 

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1.5	Mineral Resources

 

1.5.1

Archimedes Underground

Practical Mining LLC estimated the Archimedes Underground mineral resource using all drilling and geological data available through October 31, 2022. Wood Canada Ltd. estimated and reported open pit mineral resources in the inaugural NI 43-101 Technical Report under i-80’s ownership of the Ruby Hill Project. All work, including drilling, done since the time of the inaugural report has targeted the 426, Ruby Deeps and other underground deposits and does not influence the Open Pit mineral resource reported on the October 2021 report. The open pit mineral resources reported in October 2021 are current and are restated herein.

Table 1-1: Summary of Archimedes Underground Mineral Resources at the End of the Fiscal Year Ended December 31, 2024

 

Deposit		Tonnes (000)		Au (g/t)		Ag (g/t)		Au oz (000)		Ag oz (000)
Indicated Mineral Resources
426		899		6.9		0.8		199		22
Ruby Deeps		892		8.3		2.4		237		69
Total Indicated		1,791		7.6		1.6		436		92
Inferred Mineral Resources
426		1,038		6.6		1.2		219		40
Ruby Deeps		3,150		7.6		2.4		769		246
Total Inferred		4,188		7.3		2.1		988		286

Notes:

1.

Underground mineral resources have been estimated at a gold price of $2,175 per troy ounce and a silver price of $27.25 per ounce (Section 16.1).

2.

Mineral resources have been estimated using pressure oxidation gold metallurgical recoveries of 96.8% and 89.5% for the 426 and Ruby Deeps deposits respectively.

3.

Pressure oxidation cutoff grades are 5.06 and 5.48 Au g/t (0.148 and 0.160 opt) for the 426 and Ruby Deeps deposits respectively.

4.

Detailed input mining, processing, and G&A costs are defined in Section 18.1.

5.

Units shown are metric.

6.

The contained gold ounces estimates in the mineral resource table have not been adjusted for metallurgical recoveries.

7.

Numbers have been rounded as required by reporting guidelines and may result in apparent summation differences.

8.

A mineral resource is a concentration or occurrence of solid material of economic interest in or on the Earth’s crust in such form, grade or quality and quantity that there are reasonable prospects for eventual economic extraction. The location, quantity, grade or quality, continuity and other geological characteristics of a mineral resource are known, estimated or interpreted from specific geological evidence and knowledge, including sampling.

9.

An inferred mineral resource is that part of a mineral resource for which quantity and grade or quality are estimated on the basis of limited geological evidence and sampling. Geological evidence is sufficient to imply but not verify geological and grade or quality continuity. An inferred mineral resource has a lower level of confidence than that applying to an 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.

10.

Mineral resources, which are not Mineral Reserves, do not have demonstrated economic viability. The estimate of mineral resources may be materially affected by environmental, permitting, legal, title, socio-political, marketing, or other relevant factors.

11.

Mineral resources have an effective date of December 31, 2024.

12.

The reference point for mineral resources is in situ.

 

 

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1.5.2

Archimedes Open Pit

The Archimedes deposit was previously mined by Homestake and Barrick for West Archimedes and East Archimedes respectively. Mining ceased after a pit wall failure. In this study an updated estimation of the Archimedes mineral resource has been developed Forte Dynamics, Inc (Forte), and the mining potential for continuing the surface exploitation of the deposit was evaluated to estimate a current open pit mineral resource estimate.

The Archimedes mineral resources are detailed in Table 1-2. Mineral resources are not Mineral Reserves and have not been demonstrated to have economic viability. There is no certainty that the mineral resource will be converted to Mineral Reserves. Inferred mineral resources do not have sufficient confidence that modifying factors can be applied to convert them to mineral reserves. The quantity and grade or quality is an estimate and is rounded to reflect the fact that it is an approximation. Quantities may not sum due to rounding.

Table 1-2: Summary of Archimedes Open Pit Mineral Resources at the End of the Fiscal Year Ended December 31, 2024

 

Deposit		Cutoff Au (g/t)		Tonnes (000)		Au (g/t)		Ag (g/t)		Au oz (000)		Ag oz (000)
Indicated Mineral Resources
Archimedes Pit		0.2		4,280		1.98		10.7		272		1,460
		0.1		4,320		1.96		10.6		272		1,490
		0.05		4,340		1.95		10.6		272		1,480
Inferred Mineral Resources
Archimedes Pit		0.2		820		1.18		8.9		31		230
		0.1		870		1.12		8.5		31		250
		0.05		880		1.11		8.5		31		250

Notes:

1.

Mineral resources have an effective date of December 31, 2024.

2.

Mineral resources are the portion of Mineral Point that can be mined profitably by open pit mining method and processed by heap leaching.

3.

Mineral resources are below an updated topographic surface (below Archimedes pit).

4.

Mineral resources are constrained to economic material inside a conceptual open pit shell. The main parameters for pit shell construction are a gold price of $2,175/oz Au, a silver price of $26.00/oz, average gold recovery of 77%, average silver recovery of 40%, open pit mining costs of $3.31/tonne, heap leach average processing costs of $3.47/tonne, general and administrative cost of $0.83/tonne processed, gold refining cost of $1.85/oz, silver refining cost of $0.50, and a 3% royalty (Section 16.1).

5.

Mineral resources are reported above a 0.1 g/t Au cutoff grade. Silver revenues were not considered in the cutoff grade.

6.

Mineral resources are stated as in situ.

7.

Mineral resources have not been adjusted for metallurgical recoveries.

8.

Reported units are metric tonnes.

9.

Reported table numbers have been rounded as required by reporting guidelines and may result in summation discrepancies.

 

 

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1.5.3

Mineral Point Open Pit

Forte reviewed the Mineral Point Open Pit mineral resource estimate completed by Wood in July 2021. The scope of the review included the informing drillhole and sample data, exploratory data analysis (EDA), input models, and the current topography. The scope also included a review of the grade estimation methodology and model validation, bulk density determination, resource classification, reasonable prospects for eventual economic extraction (RPEEE), and the statement of mineral resources.

Upon completion of the Mineral Point open pit resource review, Forte made some slight modifications to the Wood block model. Note that the estimated block grades were not altered or changed. Updates included updating the block model with the current topographic surface, recoding the Wood 2021 lithological model to the block model along with an assigned specific gravity (SG) values based on lithology code, and updated values and conversions for tonnage factor. Forte also used an updated pit shell to constrain and report the mineral resource under the requirements for RPEEE, which was based on a 2024 Scoping Study completed by Forte and used for other work completed in this Technical Report Summary.

The Mineral Point Open Pit mineral resources are detailed in Table 1-3. Mineral resources are not mineral reserves and have not been demonstrated to have economic viability. There is no certainty that the mineral resource will be converted to mineral reserves. Inferred mineral resources do not have sufficient confidence that modifying factors can be applied to convert them to mineral reserves. The quantity and grade or quality is an estimate and is rounded to reflect the fact that it is an approximation. Quantities may not sum due to rounding.

Table 1-3: Summary of Mineral Point Open Pit Mineral Resources at the End of the Fiscal Year Ended December 31, 2024

 

Deposit		Tonnes (000)		Au (g/t)		Ag (g/t)		Au oz (000)		Ag oz (000)
Indicated Mineral Resources
Mineral Point		216,982		0.48		15.0		3,376		104,332
Total Indicated		216,982		0.48		15.0		3,376		104,332
Inferred Mineral Resources
Mineral Point		194,442		0.34		14.6		2,117		91,473
Total Inferred		194,442		0.34		14.6		2,117		91,473

Notes:

1.

Mineral resources have an effective date of December 31, 2024.

2.

Mineral resources are the portion of Mineral Point that can be mined profitably by open pit mining method and processed by heap leaching.

3.

Mineral resources are below an updated topographic surface.

4.

Mineral resources are constrained to economic material inside a conceptual open pit shell. The main parameters for pit shell construction are a gold price of $2,175/oz Au, a silver price of $26.00/oz, average gold recovery of 77%, average silver recovery of 40%, open pit mining costs of $3.31/tonne, heap leach average processing costs of $3.47/tonne, general and administrative cost of $0.83/tonne processed, gold refining cost of $1.85/oz, silver refining cost of $0.50, and a 3% royalty (Section 16.1).

5.

Mineral resources are reported above a 0.1 g/t Au cutoff grade.

6.

Mineral resources are stated as in situ.

7.

Mineral resources have not been adjusted for metallurgical recoveries.

8.

Reported units are metric tonnes.

9.

Reported table numbers have been rounded as required by reporting guidelines and may result in summation discrepancies.

 

 

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1.6	Mining, Infrastructure, and Project Schedule

 

1.6.1

Archimedes Underground

Permitting approval for development and mining above the 5100 elevation is anticipated by the end of Q2 2025 and underground development will commence immediately thereafter. This is consistent with previously approved permits for mining the Archimedes open pits. Production mining in the 426 deposit will start in 2026 and continue through 2027 with oxide material processed on site in the existing heap leach facility and refractory material sent to a third party for toll processing. Permits for mining below the 5100 elevation are anticipated in the second quarter of 2027 with development mining for the Ruby Deeps deposit beginning shortly thereafter.

Mining conditions anticipated are typical for northern Nevada underground mines. Long hole open stoping will be the primary mining method and will be supplemented with underhand drift and fill mining where deposit geometry dictates. Mining will be undertaken by a qualified contractor, eliminating the need to recruit a workforce and purchase mining equipment.

Transportation, electrical and support infrastructure already exists at Ruby Hill. Additional infrastructure requirements are limited to:

 

●

Overhead power line and transformer at the portal site.

●

Backfill and shotcrete plants.

●

Fuel and oil storage near the portal.

●

Contractor’s maintenance facility and office.

●

Mine water supply tank.

 

1.6.2

Archimedes Open Pit

The Archimedes Open Pit mineral resource has not been evaluated for surface mining.

 

1.6.3

Mineral Point Open Pit

The Mineral Point Project, operated by i-80 Gold, is planned as an open pit mining operation using conventional equipment, targeting a processing rate of 68,000 tons per day. While there is currently no Mineral Reserve Estimate, the project contains indicated and inferred mineral resources. Pit optimization using Hexagon Mine Plan software identified an optimal pit shell (LG72) with a 78% revenue factor, containing 4.98 million ounces of gold and 195.5 million ounces of silver at an average stripping ratio of 2.8:1. Key economic parameters include a gold price of $2,175/toz, silver price of $27.25/toz, and heap leach average recovery rates of 78% for gold and 41% for silver. The calculated cutoff grade for gold is 0.011 oz/ton, ensuring the extraction of economically viable material.

The mine design consists of nine pit phases, with mining benches at 50-foot intervals and a projected Life-of-Mine (LOM) of 17 years. The operation will rely on a mining fleet comprising two rope shovels, (2) hydraulic shovels, (26) haul trucks, and various support equipment. Annual production is expected to average 4.5 million ounces of gold and 177.3 million ounces of silver. Dewatering will be required in later mine stages, though the extent is yet to be determined.

The project will leverage existing infrastructure from previous mining activities at the Ruby Hill site, including site access, haul roads, waste rock storage, and power supply, with necessary upgrades. Key processing facilities include a crushing and stacking system, a heap leach pad, and a Merrill Crowe plant for gold and silver recovery. The heap leach facility will be developed in five phases, with a total capacity of 466.8 million

 

 

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tons, while a Merrill Crowe plant will process pregnant leach solution at a rate of 11,500 gallons per minute, ultimately producing doré bars for off-site refining.

Supporting infrastructure includes an expanded truck shop, warehouse, administration building, and water management systems for process, potable, fire suppression, and stormwater control. Power will be sourced from an existing substation with potential upgrades, and site communications will be maintained through telemetry and radio networks. Waste rock storage will utilize both surface storage and in-pit backfilling. Environmental considerations include stormwater management ponds, lined heap leach pads, and containment systems for fuel and hazardous materials. Road expansions and rerouting will be necessary to accommodate mining activities, ensuring operational efficiency while minimizing environmental impact.

 

1.7	Economic Analysis

Economic analysis relies on many forward-looking assumptions for the estimation of metal prices, capital and operating costs. These are subject to change depending on operating strategy, new information collected through future operations and macroeconomic conditions. Actual economic outcomes often deviate significantly from forecasts.

 

1.7.1

Archimedes Underground

The economic model is based on a mine plan that includes 69% inferred mineral resources. The results obtained excluding inferred material is a gross adjustment. Recalculation of capital and operating costs has not been included in the scenario excluding inferred mineral resources. The values presented are derived from a constant dollar after tax cash flow analysis. Capital and operating costs are summarized below in Table 1-4 and financial statistics are presented in Table 1-5.

Table 1-4: Capital and Operating Cost Summary

 

Category		Total Cost $M		$/ton Processed		$/Au oz
Costs Without Inferred
Mining		$223		$147.74		$801
Processing and Transportation		$204		$135.51		$735
G&A, Royalties and Net Proceeds Tax		$133		$87.99		$477
By Product Credits		($0.2)		($0.13)		($1)
Total Cash Cost		$560		$377.11		$2013
Closure and Reclamation		$8.9		$5.89		$32
Sustaining Capital		$106		$70.36		$382
All in Sustaining Costs		$646		$447.37		$2,427
Construction Capital		$49		$32.75		$178
All in Costs		$724		$480.12		$2,604
Cost With Inferred
Mining		$750		$148.98		$808
Processing and Transportation		$682		$135.51		$735
G&A, Royalties and Net Proceeds Tax		$210		$41.80		$227
By Product Credits		($0.7)		($0.1)		($1)
Total Cash Cost		$1,642		$326.17		$1,769
Closure and Reclamation		$8.9		$1.77		$10
Sustaining Capital		$106		$21.08		$114
All in Sustaining Costs 2		$1,757		$349.01		$1,893
Construction Capital		$49		$9.81		$53
All in Costs 3		$1,806		$358.82		$1,946

 

 

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Table 1-5: Financial Statistics

 

Parameter		Value With   Inferred		Value  Without   Inferred
Gold Price (US$/oz)		$2,175		$2,175
Silver Price (US$/oz)		$27.25		$27.25
Mine Life (years)		10		10
Mining Rate (tons/day)		1,600		450
Tons Processed Autoclave (kton)		4,846		1,452
Average Grade Autoclave (Au oz/ton)		0.209		0.209
Average Gold Recovery (Autoclave %)		90%		90%
Autoclave Gold Produced (koz)		910		272
Tons Processed Heap Leach (kton)		188		56
Average Grade Heap Leach (Au oz/ton)		0.111		0.111
Average Gold Recovery (Heap Leach %)		87%		87%
Heap Leach Gold Produced (koz)		18		5.5
Average Annual Gold Production (koz)		102		31
Total Recovered Gold (koz)		928		278
Project After-Tax NPV5% (M$)		$127		($113)
Project After-Tax NPV8% (M$)		$91		($109)
Project After-Tax IRR		23%		NA
Payback Period		7.8 Years		NA Years

Notes:

1.

Net of byproduct sales.

2.

Excludes, construction capital, exploration, corporate G&A, interest on debt, and corporate taxes.

3.

Excludes exploration, corporate G&A, interest on debt, and corporate taxes.

4.

The financial analysis contains certain information that may constitute “forward-looking information” under applicable United States and Canadian securities legislation. Forward-looking information includes, but is not limited to, statements regarding the Company’s achievement of the full-year projections for ounce production, production costs, AISC costs per ounce, cash cost per ounce and realized gold/silver price per ounce, the Company’s ability to meet annual operations estimates, and statements about strategic plans, including future operations, future work programs, capital expenditures, discovery and production of minerals, price of gold and currency exchange rates, timing of geological reports and corporate and technical objectives. Forward-looking information is necessarily based upon a number of assumptions that, while considered reasonable, are subject to known and unknown risks, uncertainties, and other factors which may cause the actual results and future events to differ materially from those expressed or implied by such forward looking information, including the risks inherent to the mining industry, adverse economic and market developments and the risks identified in the Company’s annual information form under the heading “Risk Factors”. There can be no assurance that such information will prove to be accurate, as actual results and future events could differ materially from those anticipated in such information. Accordingly, readers should not place undue reliance on forward-looking information. All forward-looking information contained in this report is given as of the date hereof and is based upon the opinions and estimates of management and information available to management as at the date hereof. The Company disclaims any intention or obligation to update or revise any forward-looking information, whether as a result of new information, future events or otherwise, except as required by law.

 

1.7.2

Mineral Point Open Pit

The economic analysis of the Mineral Point Project is based on the mine schedule, capital and operating costs, metal recovery parameters, and royalties. The project, operated by i-80 Gold, is planned as an open pit operation with a processing rate of 68,000 tons per day. The economic model assumes a gold price of $2,175/oz and a silver price of $27.25/oz, with a total initial capital investment of $708 million and sustaining capital of $388 million. In addition, approximately 115 million tons of stripping is required to gain access to the body of mineralized material, costing $287 million. The life-of-mine (LOM) plan spans approximately 16.5 years, with total recovered gold and silver estimated at 3.5 million ounces and 72 million ounces, respectively. The estimated pre-tax net present value (NPV) at a 5% discount rate is $827.6 million, with

 

 

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an internal rate of return (IRR) of 13.8% and a payback period of 7.6 years. After-tax, the NPV at 5% is reduced to $614.1 million, with an IRR of 12.1% and a payback period of 7.9 years.

A sensitivity analysis indicates that the project is most sensitive to metal prices and recovery rates, followed by capital and operating costs. The inclusion of inferred resources, which constitute 38% of the mine plan, significantly impacts the economic assessment. When excluding inferred resources, the mine life is reduced to 11.5 years, and the after-tax NPV at 5% drops to $157.9 million. Under this scenario, the project becomes marginal at higher discount rates, with an IRR of 7.8% and a longer payback period of 8.9 years. While the Mineral Point Project demonstrates economic potential, additional exploration and refinement of cost estimates are necessary to improve confidence in the resource model and the feasibility of long-term operations. Table 1-6 shows the total and unit operating costs with and without inferred. Table 1-7 shows the financial with and without inferred.

Table 1-6: Unit and Total Operating Costs With and Without Inferred Resources

 

Category		Total Cost $M		$/ton Processed		$/Au oz
Costs With Inferred
Mining		$3,874.40		$9.80		$1,097.75
Processing		$1,542.23		$3.90		$436.97
G&A		$296.58		$0.75		$84.03
Refining, Royalties & Net Proceeds Tax		$722.30		$1.83		$204.65
By-Product Credits		$(1,952.96)		$(4.94)		$(553.34)
Total Operating Cost/Cash Costs		$4,482.57		$11.34		$1,270.07
Closure & reclamation		$69.83		$0.18		$19.78
Sustaining Capital		$388.43		$0.98		$110.05
All-in Sustaining Costs		$4,940.82		$12.49		$1,399.91
Cost Without Inferred
Mining		$2,213.49		$11.15		$1,124.31
Processing		$774.50		$3.90		$393.40
G&A		$148.94		$0.75		$75.65
Refining, Royalties & Net Proceeds Tax		$374.27		$1.88		$190.10
By-Product Credits		$(851.57)		$(4.29)		$(432.54)
Total Operating Cost/Cash Costs		$2,659.63		$13.39		$1,350.92
Closure & reclamation		$67.33		$0.34		$34.20
Sustaining Capital		$131.48		$0.66		$66.78
All-in Sustaining Costs		$2,858.44		$14.39		$1,451.90

 

 

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Table 1-7: After-Tax NPV Comparison of With and Without Inferred Resources

 

Parameter		Unit		Value With  Inferred		Value Without  Inferred
Mine Life		year		16.5		11.5
Mining Rate		kton/day		356.2		328.8
Processing Rate		kton/day		68.4		49.3
Total Processed Material		kton		395,444		195,591
Total Mine Material		kton		1,675,243		987,993
Average Processing Grade Au		toz/ton		0.011		0.012
Average Processing Grade Ag		toz/ton		0.448		0.383
Contained Au		ktoz		4,525		2,430
Contained Ag		ktoz		177,293		76,109
Recovered Au		ktoz		3,529		1,969
Recovered Ag		ktoz		72,028		31,407
Heap Leach Recovery Au (average)		%		78%		81%
Heap Leach Recovery Ag (average)		%		41%		41%
Total LOM CAPX		US$M		$1,383.2		$941.2
NPV @ 0%		US$M		$1,470.0		$574.1
NPV @ 5%		US$M		$614.1		$157.9
NPV @ 8%		US$M		$295.8		$(10.9)
NPV @ 10%		US$M		$134.8		$(100.1)
NPV @ 12%		US$M		$4.3		$(174.8)
IRR		%		12.1%		7.8%
Payback Period		Year		7.6		7.9

 

1.8	Conclusions

 

1.8.1

Archimedes Underground

 

1.8.1.1

Mineral Resources

The Archimedes Underground mineral resource contains approximately 70% inferred mineral resources. The planned underground development and drilling program is planned to upgrade inferred mineral resources to indicated.

 

1.8.1.2

Mining and Infrastructure

Mining conditions for the Archimedes underground are typical for sedimentary deposits in the north-east Nevada extensional tectonic environments are anticipated. The Ruby Deeps deposit will require dewatering with anticipated pumping rates of 500 to 1,000 gpm.

 

1.8.1.3

Metallurgical Testing

Metallurgical testing of refractory samples from Archimedes underground deposits has confirmed amenability to grinding followed by pressure oxidation and carbon in leach. Gold recoveries ranged from 80% to 91%. Metallurgical testing programs have identified deleterious elements that are common to deposits in this part of Nevada. Deleterious elements content in the oxide samples are low, while sulfide samples are characterized by high levels of sulfide sulfur, arsenic, and mercury. Processing of Archimedes sulfide mineralization through a third-party or i-80’s Lone Tree autoclave will ensure removal and capture of these deleterious elements.

 

1.8.1.4

Recovery Methods

Metallurgical testing has confirmed that processing of Archimedes underground sulfide mineralization can be processed through Nevada Gold Mines Twin Creeks or the Lone Tree autoclave facilities. The 426 mineralized lenses are more amenable to alkaline conditions while the Ruby Deeps lenses perform better with acidic conditions.

 

 

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1.8.1.5

Financials

 

●

Initial capital requirements total $49.4M with an additional $106.1M in sustaining capital.

●

The project achieves after-tax NPV 5% of $126.8M and NPV 8% of $91.1M.

●

The estimated payback period is 7.8 years with an IRR of 23%.

 

1.8.2

Archimedes Open Pit

 

1.8.2.1

Mineral Resources

The Archimedes deposit was previously mined by Homestake and Barrick for West Archimedes and East Archimedes respectively. Mining ceased after a pit wall failure. An updated mineral resource estimate was completed, with the majority of mineral resources classified as indicated. There is currently potential for additional surface production of the deposit which would add to the value of the overall Ruby Hill project.

As the pit was never restarted after the wall failure, it will be important to understand and mitigate rock mechanics stability and safety issues prior to any decision to restart the project.

Given the current focus on the underground mine and the Mineral Point pit, no additional work in the Archimedes pit has been planned.

 

1.8.3

Mineral Point Open Pit

 

1.8.3.1

Mineral Resources

The Mineral Point Open Pit mineral resource contains approximately 47% inferred mineral resources. Drilling is planned for the deposit to obtain fresh material for additional metallurgical testing. The additional metallurgical test results can be used in future work, along with additional testing for representative bulk density measurements to be used with future updated geological, alteration, redox and structural models. This can be used for future mineral resource updates and potentially upgrading inferred mineral resources to indicated mineral resources.

 

1.8.3.2

Mining and Infrastructure

Mineral point will be a large-scale open pit gold and silver deposit typical of other northern Nevada mines with stripping ratio of 2.9:1, excluding capitalized pre-stripping. Overall average gold grade processed of 0.39 g/tonne with an expected average gold recovery of 78% and an average silver grade processed of 15.37 g/tonne. Most of the current infrastructure on site can be re-used or expanded for the project. Power for the proposed operation will be provided by the power supplier that historically fed the site.

 

1.8.3.3

Metallurgical Testing

Historical metallurgical testing and production have confirmed the amenability of Mineral Point open pit oxide and sulfide mineralization to conventional cyanide heap leaching; Metallurgical testing of samples from the Mineral Point open pit deposit has also shown amenability to crushing for heap leaching. Gold and silver recoveries ranged from 80-85% and 32-45% respectively.

 

1.8.3.4

Recovery Methods

Oxide and sulfide material is amenable for processing by crushed-ore cyanide heap leaching. Gold and silver leach at the heap-leach facility will be extracted by Merrill-Crowe zinc precipitation.

 

1.8.3.5

Financials

 

●

Total capital requirement of $1,383.2M

●

The project achieves an NPV 5% of $614.1M and NPV 10% of $134.8M After-Tax

 

 

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●

The project has and IRR of 12.1% and a payback period of 7.9 years After-Tax

 

1.9	Recommendations

 

1.9.1

Archimedes Underground

 

1.9.1.1

Metallurgical Testing

 

●

Additional metallurgical testing is recommended from initial Ruby Hill production areas to confirm metallurgical recoveries with Twin Creeks process conditions. Sample selection should be based on available mine production plans and should reflect typical stope dimensions and expected dilution. Testing should include:

•

Comminution testing to confirm throughput through the Sage Mill.

•

Pressure oxidation tests using Twin Creeks conditions.

•

CIL tests on pressure oxidation productions.

 

●

Additional testing on Ruby Hill base metal sulfide zones to investigate flotation parameters to produce saleable lead and zinc concentrates. Detailed assays of lead and zinc concentrates are recommended to determine the extent of deleterious elements that may impair their salability.

 

1.9.1.2

Permitting and Mine Development

 

●

Complete the EA and POO amendment for Mining the 426 deposit above the 5100 elevation.

●

Initiate construction of the haulage portal and decline in Q3 2025.

 

1.9.1.3

Resource Conversion and Exploration Drilling

 

●

Begin Resource Conversion Drilling as soon as decline advance and drill platforms become available.

●

The lower leg of the decline provides a drill platform for exploration of the Blackjack deposit.

 

1.9.1.4

Dewatering

 

●

Initiate a hydrogeologic study of the Windfall formation, drill a deep test well and complete a drawdown test.

 

1.9.2

Archimedes Open Pit

Due to the short-term development plans for Mineral Point Open Pit and Archimedes Underground, additional work for the Archimedes Open Pit is not currently defined. Should resources be available a detailed geotechnical review of the existing pit slopes in Archimedes could help to quantify future potential. In light of current development plans on the property, this is not budgeted at this time.

 

1.9.3

Mineral Point Open Pit

 

1.9.3.1

Mineral Resources

It is recommended that i-80 complete additional resource definition drilling and conduct a review of major and minor rock alteration types, and how they align with overall geology, grade domains, metallurgical recovery and bulk densities. This would also include review of the geological model, including lithological, structural, and alteration controls on overall grade distribution and metallurgical recovery. The additional drilling could be used to better define the limits of mineralization and potentially upgrades block classification.

 

 

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The following points are recommended for additional evaluation:

 

●

Review of the overall (and subsequent low and high-grade) grade distributions to better understand impacts on mineralized domains.

●

Detailed review of deposit wide bulk densities to better define the bulk density for the project, including bulk densities of lithology and alteration type.

●

Additional drilling to increase the resource definition and confidence, along with potential upgrading of resource classification (inferred to indicated, indicated to measured).

●

Additional drilling for potential resource expansion.

Upon completion of the above items, an update to the geological model and mineral resource estimate should be conducted, along with updated metallurgical recovery assumptions.

 

1.9.3.2

Mining and Infrastructure

It is recommended that a site wide water balance be developed for the project to better understand water captured on-site (pit, HLP, WRSA) and evaluate the ability to utilize this water for process make-up water or to provide water for agriculture use. This would include evaluation of climate and available make-up water sources to understand total project requirements for make-up water or discharge as required. The evaluation would include a more accurate reflection of drain down for events, and potentially reduce the event pond volumes required, which could impact capital and sustaining capital costs.

There are several opportunities for infrastructure related components of the project to evaluate, including:

 

●

Conveyor stacking versus truck stacking, reduction of capital and operating costs.

●

Blasting versus crushing and screening, reduction of capital and operating costs.

●

Reduced number of event ponds and utilize larger event ponds to reduce capital costs.

●

Increased Heap Ultimate height of 300 feet, reduction of disturbance area as well as capital costs.

●

Utilization of existing crusher to self-perform overliner manufacturing to reduce capital costs

●

Evaluate all pits for potential for pit dewatering, including water quality evaluation, for ability to utilize this water as process make-up water or for agricultural use.

 

1.9.3.3

Metallurgical Testing

It is recommended that additional metallurgical testing be conducted to further define the predicted recovery for the Mineral Point Open pit project. This includes evaluation of sulfide sulfur content which will assist with determining the various oxidations by lithology as well as understanding recovery and reagent consumptions. This should also be conducted for waste as there may be a need to segregate waste into PAG and NAG facilities.

Next phases of the metallurgical testing program would incorporate additional leach tests, coarse bottle rolls, and column leach tests. This testing is required to support crush size selection, recovery estimates and reagent consumptions for lime and cyanide. Testing is also required to provide comminution design data. Testing and samples to be tested include:

 

●

Samples should focus on weakly-altered alteration of the major formations, the largest component of the Mineral Point resources. Sample selection should address spatial and grade variability within the deposit.

●

Identify samples in transition areas to sulfide mineralization to establish boundary criteria such as sulfide sulfur content.

●

Use of PQ diameter drilling will permit testing up to -2” crush size to evaluate the impact of crush size on recoveries.

 

 

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●

Evaluate the pilot leach testing of a bulk sample to determine ROM recoveries.

 

●

Testing of composite samples representing the first year and second year mine production once optimal conditions are selected.

 

●

Conduct column leach tests with taller columns and columns in series to replicate actual lift heights and heap leach operations.

 

●

Conduct laboratory tests to determine the crusher work index and abrasion indices to support crushing plant design.

 

●

Geotechnical testing, namely compacted permeability testing, of samples to determine the permeability and stacking characteristics of the mineralized material.

 

●

ABA testing of leach residue under conditions to support environmental permitting.

Additional considerations include metallurgical and geotechnical testing which will further the understanding of the ore’s clay content. This would include particle size distribution analysis, Atterberg limits, plasticity index, by ore type. This would also be coupled with compacted permeability testing to understand long term effects of loading and stacking. It is also recommended that ore decrepitation testing be conducted. Additional evaluation of the outcomes of this testing will verify the proposed application rate, leach cycle, and stack height for the various oxidations and lithologies based on permeability and agglomeration requirements.

It is also recommended that additional testing of proposed overliner material be conducted to evaluate screening requirements as well as stability for geotechnical design. This could also lead to a reduction in the overliner depth requirement, decreasing capital costs for the project.

Additional test work for recovery potential of the relocated HL material from historic operations should be conducted to potentially include revenue from this material.

The program has an estimated cost of $600,000 (excluding drilling costs) based on current conditions.

 

1.9.4

Work Programs

 

1.9.4.1

Archimedes Underground

The work program outlined in Table 1-8 will advance the 426 deposit to production within two years. Project risks are manageable, and opportunities exist to enhance the project economics.

Table 1-8: Archimedes Underground Work Program

 

Description		2025					2026					Estimated   Costs  (US$M)
Portal Construction				0.1					0.1					0.2
Mine Development				7.8					21.0					28.8
Resource Conversion Drilling				2.1					-					2.1
Dewatering Well and Hydrogeologic Study				3.9					-					3.9
Environmental, Metallurgical Testing and Feasibility Study				0.5					2.0					2.5
Ventilation and Electrical				0.2					2.7					2.9
Project Administration				5.0					0.6					5.6
Contingency				2.9					4.5					7.4
Total				22.5					30.8					53.3

 

 

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