Financial Report (goro ex 96 ddgm 2025 sk 1300)

Exhibit 96.2

S-K 1300 Technical Report Summary on the Don David Gold Mine Project, Oaxaca, Mexico

Report prepared for: Report Date:

GOLD RESOURCE CORPORATION March 18, 2026

Report prepared by: Effective Date:

Rodrigo Simidu, P.Eng. December 31, 2025 Marcelo Zangrandi, MAIG

Christian Laroche, P.Eng.

David Turner, MAIG

Table of Contents

Page No

1. Executive Summary 1

   1. Introduction 1

   2. Qualified Persons (QPs) 1

   3. Property Description, Location, and Ownership 3

   4. History 3

   5. Geology Setting, Mineralization, and Deposit 4

   6. Exploration 4

   7. Data Verification 5

   8. Mineral Processing and Metallurgical Testing 5

   9. Commodity Price Projections 6

   10. Mineral Resources Estimates 7

   11. Mineral Reserves Estimates 8

   12. Mining Methods 9

   13. Processing And Recovery Methods 10

   14. Project Infrastructure 10

   15. Market Studies and Contracts 10

   16. Environmental Studies, Permitting and Plans, Negotiations, or Agreements with Local Individuals or

       Groups. 11

   17. Capital and Operating Costs 11

   18. Economic Analysis 11

   19. Interpretations and Conclusions 12

   20. Recommendations 12

2. Introduction 12

   1. Report Purpose 12

   2. Qualified Persons 12

   3. Effective Date 13

   4. Previous Technical Reports 13

   5. Information Sources and References 13

3. Property description and location 14

   1. Mineral Tenure 14

   2. Surface Rights 17

   3. Royalties 17

   4. Environmental Aspects 18

   5. Permits 18

   6. Other Significant Factors and Risks 18

   7. Comment on Section 3 18

4. Accessibility, Climate, Local Resources, Infrastructure and Physiography 19

   1. Access 19

   2. Climate 19

   3. Topography, Elevation and Vegetation 19

   4. Infrastructure 19

   5. Sufficiency of Surface Rights 20

   6. Comment on Section 4 20

5. History 21

   1. Ownership History 21

   2. Exploration History 21

   3. Prior Mineral Resources and Mineral Reserves 21

   4. Production History 21

6. Geological Setting and Mineralization and Deposit 23

   1. Regional Geology 23

Page No

12.11 Opinion of the Qualified Person 154

1. Mining Methods 155

   1. Hydrogeology 155

   2. Mine Geotechnical 155

   3. Surface Mining 156

   4. Underground Mining 157

   5. Mine Production Schedule 164

   6. Equipment, Manpower and Services 166

2. Recovery Methods 175

   1. DDGM Processing Facility 175

   2. Crushing and Milling 178

   3. Differential Flotation 178

   4. Agitated Leaching 180

   5. Tailings and Water Management 180

   6. Laboratory Facilities 182

3. Project Infrastructure 192

   1. Roads 192

   2. Tailing Disposal Facilities 192

   3. Mine Waste Stockpiles 193

   4. Ore Stockpiles 193

   5. Concentrate Transportation 193

   6. Power Generation 193

   7. Water 194

   8. Offices and Buildings 195

   9. Core Storage Facility 196

   10. Communications systems 197

   11. Opinion of Qualified Person 197

4. Market Studies and Contracts 197

   1. Market studies 197

   2. Contracts 198

   3. Concentrate Sales 198

   4. Commodity Price Projections 198

   5. Comment on Section 16 199

5. Environmental Studies, Permitting, and Plans, Negotiations or Agreements with Local Individuals or Groups 200

   1. Environmental Compliance and Considerations 200

   2. Solid Waste Disposal 204

   3. Water and Air Sampling 204

   4. Mine Closure Plan 204

   5. Ejido Lands and Surface Rights Acquisitions 208

   6. Social or Community Impact 208

   7. Community Actions for Social Welfare and Development 209

   8. Opinion of Qualified Person 211

6. Capital and Operating Costs 211

   1. Life-Of-Mine Capital Costs 211

   2. Life-Of-Mine Operating Costs 212

      19.1	Economic Analysis	213
      19.2	Taxes	216

7. Economic Analysis 213

8. Adjacent Properties 217

   1. GRC Properties 217

   2. Third-Party Properties 217

9. Other Relevant Data and Information 217

   Page No

10. Interpretation and Conclusions 217

    1. Property Description, Location and Ownership 217

    2. Geology and Mineralization 217

    3. Exploration, Drilling and Sampling 218

    4. Data Verification 220

    5. Mineral Processing and Metallurgical Testing 221

    6. Mineral Resources 221

    7. Mineral Reserves 222

    8. Mining Methods 222

    9. Recovery Methods 223

    10. Project Infrastructure 223

    11. Market Studies and Contracts 224

    12. Environmental Studies, Permitting, Social and Community Impact 224

    13. Capital and Operating Costs 224

    14. Economic Analysis 225

    15. Risks and Opportunities 225

11. Recommendations 226

    1. Mineral Processing 226

    2. Recovery Methods 226

    3. Mining Methods 226

    4. Exploration 226

    5. Mine Closure Plan 228

    6. Risks and Opportunities 228

12. References 229

13. Reliance on Information Provided by the Registrant 232

Table 1 1: Summary of QP Qualifications. 2

Table 1 2: Summary of DDGM Properties. 3

Table 1 3: Mineral estimation Commodity Price Projections. 6

Table 1 4: Economic Analysis Commodity Price Projections. 6

Table 1 5: Don David Gold Mine (Arista Mine) - Summary of Gold, Silver and Base Metal Mineral Resources, exclusive of Mineral

Reserves at December 31, 2025. 8

Table 1 6: Don David Gold Mine (Alta Gracia Mine) - Summary of Gold, Silver and Base Metal Mineral Resources, exclusive of Mineral

Reserves at December 31, 2025. 8

Table 1 7: Don David Gold Mine - Summary of Gold, Silver and Base Metal Mineral Reserves at December 31, 2025. 9

Table 3 1: Mining Concessions Owned by Don David Gold Mexico, S.A. de C.V. 15

Table 3 2: Don David Gold Mine Concession Maintenance Fees by Property. 17

Table 5 1: Don David Mine Production 2010 through 2025. 22

Table 7 1: Regional Anomalies - Location and Geology (Jaacks, 2007). 43

Table 7 2: Regional Anomalies Geochemistry (Jaacks, 2007). 43

Table 7 3: Summary of Soil Geochemistry programs undertaken by GRC from 2012 to 2023. 45

Table 7 4: Summary of Petrographic Thin and Polished section Studies. 48

Table 7 5: Don David Mine Exploration Drilling Activity through December 31, 2025. 51

Table 7 6: Significant 2025 Drilling Results for the Arista Mine. 69-71

Table 8 1: List of routine process sampling, the analysis performed, and reporting frequency. 75

Table 10 1: Concentrate Pressure Filtration Study Results (from Lyntek). 81

Table 10 2: Slurry Analysis. 82

Table 10 3: Slurry Solids Minerology. 83

Table 10 4: Process Water Constituents and Characteristics. 84

Table 10 5: Test Result for Flowability. 84

Table 10 6: Pressure Filtration - Dry Specific Cake Weight as a Function of Cake Thickness. 85

Table 10 7: Pressure Filtration - Form Time as a Function of Dry Specific Cake Weight. 86

Table 10 8: Pressure Filtration - Form Cake Moisture Content as a Function of Form Time. 86

Table 10 9: Pressure Filtration - Dry Time Factor as a Function of Final Dry Cake Moisture Content. 86

Table 10 10: Characteristics of the Copper Concentrate, Minerals Content. 89

Table 10 11: Characteristics of the Lead Concentrate, Minerals Content. 89

Table 10 12: Characteristics of the Zinc Concentrate, Minerals Content. 90

Table 11 1: Don David Gold Mine (Arista Mine) - Summary of Gold, Silver and Base Metal Mineral Resources, exclusive of Reserves at

December 31, 2025. 91

Table 11 2: Don David Gold Mine (Alta Gracia Mine) - Summary of Gold, Silver and Base Metal Mineral Resources, exclusive of Reserves

at December 31, 2025. 91

Table 11 3: Summary Assay Statistics. 95

Table 11 4: Density Capping Values. 96

Table 11 5: Vein codes used in wireframes, composites and block models. 100

Table 11 6: Univariate statistics of the major mineralized veins of Switchback vein system. 102

Table 11 7: Univariate statistics of the major mineralized veins of Arista vein system. 102

Table 11 8: Summary of general capping for Arista and Switchback. 108

Table 11 9: Composite Capping Values Inside Wire-Framed Veins of the Don David Mine. 110

Table 11 10: Summary of parameters describing grade continuity for major estimation domains. 114

Table 11 11: Block Model Specifications - Arista, Switchback and Alta Gracia models. 118

Table 11 12: Block Model Variables - Arista, Switchback and Alta Gracia models. 119

Table 11 13: Comparison between wireframes and block model tonnages. 120

Table 11 14: Example of search parameters. 125

Table 11 15: Measured and Indicated OK vs NN estimates comparison. 126

Table 11 16: Grade and tonnages at incremental cutoff grades for Arista. 138

Table 11 17: Grade and tonnages at incremental cutoff grades for Switchback. 140

Table 11 18: Grade and tonnages at incremental cutoff grades for Alta Gracia. 142

Table 11 19: Comparison of 12/31/2025 Versus 12/31/2024 Arista Mine Mineral Resources. 144

Table 11 20: Comparison of 12/31/2025 Versus 12/31/2024 Arista Mine Inferred Mineral Resources. 145

Table 11 21: Comparison of 12/31/2025 Versus 12/31/2024 Alta Gracia Mineral Resources. 145

Table 12 1: Stope Dimensions. 147

Table 12 2: External Mine Dilution. 149

Table 12 3: Mine Site Cash Operating Costs Used for Breakeven NSR Cutoff Grade Calculations. 150

Table 12 4: Parameters Used for Breakeven NSR Cutoff Grade Calculations. 151-152

Table 12 5: NSR Multiplier Values used for Breakeven Cutoff Grade Calculations. 152

Table 12 6: Don David Gold Mine - Summary of Gold, Silver and Base Metal Mineral Reserves at December 31, 2025. 153

Table 12 7: Don David Gold Mine - Summary of Gold, Silver and Base Metal Mineral Reserves at December 31, 2024. 154

Table 13 1: Arista Underground Mine Levels and Corresponding Elevation. 160

Table 13 2: Mirador Underground Mine Levels and Corresponding Elevation. 161

Table 13 3: Don David Mine Life-of-Mine Production Summary. 166

Table 13 4: Full-time, Direct Employees for the Oaxaca Mining Unit. 168

Table 16 1: 2025 Resource and reserves metal prices. 199

Table 16 2: Consensus metal prices 2026-2028. 199

Table 17 1: Don David Mine Environmental Permits and Issuing Agencies for Arista. 201

Figure 3 1: General Location of the six Properties Comprising the Don David Mine. 14

Figure 3 2: Don David Mine Concessions (concession numbers are listed in Table 3.1). 16

Figure 6 1: Map of Oaxaca State showing tectonostratigraphic terranes. 23

Figure 6 2: Concession boundaries in yellow (Geology after Sánchez Rojas et al., 2000; map insert from INEGI 2019). 24

Figure 6 3: Geologic Map of the Arista Project and Arista Underground Mine Area. 25

Figure 6 4: Stratigraphic Column for the Don David Mine Area. 26

Figure 6 5: Simplified early structural framework for the Arista System highlighting fault-vein geometries; inset photo illustrates outcrop

expression of dilation jog as favorable sites for vein/mineralization (mod. from Vos et al., 2012). 30

Figure 6 6: Generalized late structural framework, Arista System; shows post-mineralization deformation of the Arista vein system (mod.

from Vos et al., 2012). 31

Figure 6 7: Plan Map Showing Geology and Vein Targets/Prospects at the Alta Gracia Project. 33

Figure 6 8: Arista Mine Schematic Cross-Section View Looking Northwest at the Arista and Switchback Vein Systems. 35

Figure 6 9: Typical Colloform Banded Style of the Arista Vein; Arista Mine Level 6. Vein is nearly 5 m wide from foot of miner to upper

right of photo as indicated by yellow arrows. 37

Figure 6 10: Examples of mineralized quartz veins at DDGM's Don David Mine. 39

Figure 6 11: Conceptual model illustrating different styles of epithermal, magmatic arc mineralization (From Corbett, 2008). 40

Figure 7 1: Regional Stream Sediment Anomalies (Jaacks, 2007). 44

Figure 7 2: Aerial magnetic survey of Don David Mine properties. 46

Figure 7 3: 3D Voxel model section view. 47

Figure 7 4: Surface Drill Hole Location Map of the Don David Mine. 50

Figure 7 5: Drill hole traces (black lines) for completed underground drilling through December 31, 2025. 52

Figure 7 6: Plan view of the Arista, Switchback and Three Sisters vein systems showing diamond drill holes completed in 2025. 61

Figure 7 7: Plan view of the north-western Arista mine showing the Arista, Three Sisters and Switchback vein systems with diamond drilling

completed in 2024. 62

Figure 7 8: Cross section (A-AA) looking north-west through the Arista, Three Sisters and Switchback vein systems of the Arista mine

showing 2025 drilling results. 63

Figure 7 9: Cross section (B-BB) looking north-west through the Three Sisters vein system of the Arista mine showing 2025 drilling results. 64

Figure 7 10: Arista Mine, Arista Deposit section displaying mineralization, modelled vein solids and lithology. 65

Figure 7 11: Arista Mine, Switchback Deposit section displaying mineralization, modelled vein solids and lithology. 66

Figure 7 12: Alta Gracia Project, Mirador Deposit section displaying mineralization, modelled vein solids and lithology. 67

Figure 7 13: Alta Gracia Project, Independencia Deposit section displaying mineralization, modelled vein solids and lithology. 68

Figure 8 1: Sulfide (Floatation Plant) Sample Points. 74

Figure 10 1: Grade-recovery curve for copper. 79

Figure 10 2: Feed and Product Size Distribution. 80

Figure 10 3: Slurry Particle Analysis. 83

Figure 10 4: Pipeline Route for Filtered Tailings Feed Pipeline. 87

Figure 10 5: Pipeline Route from Filter Plant to Paste Plant. 88

Figure 11 1: 3D view of block model limits and drill holes. 93

Figure 11 2: Density Capping Analysis for Arista. 96

Figure 11 3: Density Capping Analysis for Switchback. 97

Figure 11 4: Three-dimensional view of the wire frame solids of the veins modeled for the Arista, Switchback and Three Sisters vein systems. 99

Figure 11 5: Three-dimensional view of the wire frame solids of the veins modeled for Resource estimation for the Alta Gracia Vein Systems. 99

Figure 11 6: Histogram of raw sample lengths in all samples from Arista (left) and from Switchback (right). 106

Figure 11 7: General capping for all Switchback vein domains. 107

Figure 11 8: General capping for all Arista vein domains. 108

Figure 11 9: Log probability plots for Au, Ag, Cu, Pb and Zn, for Selene Vein, showing the capping criteria. 109

Figure 11 10: Exclusion of distant high yield samples in Vulcan, for Ag grades estimation, Selene Vein. 111

Figure 11 11: Selene (Switchback) experimental and modelled Ag variograms. 112

Figure 11 12: Sadie 2 (Three Sisters) experimental and modelled Au variograms. 113

Figure 11 13: Block Model locations, orientations and dimensions for the Arista, Switchback, and Three Sisters Vein Systems at the Arista

Underground Mine. 121

Figure 11 14: Block Model Location, orientation, and dimension for the Alta Gracia Vein Systems. 122

Figure 11 15: Vertical cross-section of Soledad Sur vein with Ag search ellipsoids showing variable anisotropy. 123

Figure 11 16: Example of relationship between variogram range and search radii (Soledad Sur, continuity models for gold). 124

Figure 11 17: Cross mineralization average strike swath plots for Alta Gracia. 127

Figure 11 18: Cross mineralization average strike swath plots for Arista. 128

Figure 11 19: Cross mineralization average strike swath plots for Switchback. 129

Figure 11 20: Arista longitudinal vertical section showing Ag blocks versus composite grades. 130

Figure 11 21: Switchback longitudinal vertical section showing Zn blocks versus composite grades. 130

Figure 11 22: Three Sisters vertical cross section showing Au blocks versus composite grades. 131

Figure 11 23: Validation of Classification Arista. 133

Figure 11 24: Validation of Classification Switchback. 133

Figure 11 25: Validation of Classification Three Sisters. 134

Figure 11 26: Arista vertical cross section view showing the final model classification. 134

Figure 11 27: Switchback vertical cross section view showing the final model classification. 135

Figure 11 28: Three Sisters vertical cross section view showing the final model classification. 135

Figure 11 29: Plan View of Mineral Resources Exclusive of Mineral Reserves and condemned zones. 137

Figure 11 30: Grade tonnage curves for Arista. 139

1. EXECUTIVE SUMMARY
   1. Introduction

      GOLD RESOURCE CORPORATION (NYSE American: GORO) is a registrant with the United States Securities and Exchange Commission ("SEC"). GORO must report its exploration results, Mineral Resources, and Mineral Reserves using the mining disclosure standards of Subpart 229.1300 of Regulation S-K Disclosure by Registrants Engaged in Mining Operations ("S-K 1300").

      This report is a Technical Report Summary ("Technical Report") in accordance with the SEC S-K 1300 for Don David Gold Mexico S.A. de C.V. ("DDGM" or "Don David Gold Mine" or "Don David Mine" or the "Project"), a wholly owned subsidiary of Gold Resource Corporation ("GRC"). DDGM is an underground gold, silver, and base-metal production stage property with exploration prospects in Oaxaca, Mexico. This report supports the historical, scientific, and technical information concerning the Project, effective as of December 31, 2025. This report does not purport to reflect new information regarding the Project arising after such date.

      DDGM adopted S-K 1300 standards for the December 31, 2021 Technical Report. The adoption applied a new methodology focused on geological interpretations, improved grade estimation, better variable anisotropy, channel sampling, and improved grade-control models. This approach creates greater confidence in the reliability of the Mineral Resources and Mineral Reserves. Gold and silver ounces are reported in troy ounces converted using 31.1035 grams per troy ounce. Unless otherwise stated, all currency is in U.S. dollars ("$").

   2. Qualified Persons (QPs)

      The Qualified Persons ("QPs") preparing this report are mining industry professionals and specialists trained in diverse technical backgrounds, including but not limited to geology, exploration, environmental, cost estimation, and mineral economics. A QP, defined under SEC S-K 1300 instructions, is a mineral industry professional with at least five years of relevant work experience in the type of mineralization and deposit like DDGM and an eligible member or licensee in good standing of a recognized professional organization.

      By their education, experience, and professional association, the following individuals are considered QPs for this report and are members in good standing of relevant professional institutions/organizations. As noted below, two of the QPs are GRC employees; and therefore, such individuals are not independent of DDGM.

      Table 1-1 Summary of QP Qualifications.

      QP NAME & BIOGRAPHY	SITE VISIT	RESPONSIBLE SECTIONS
      Rodrigo Simidu, P.Eng. (GRC employee)
      Mr. Rodrigo Simidu graduated with a degree in Mining Engineering from the University of Sao Paulo, Brazil, in 2008. He is a Professional Engineer (P. Eng.) registered with Engineers & Geoscientists British Columbia (EGBC). Mr. Simidu has over 17 years of practical experience as a mining engineer in several mining methods for hard rock mines, with a strong background in mine planning. He is currently the principal Mining Engineer for GRC, and his relevant experience includes operational, planning, corporate technical support, and consulting in Canada, USA, Mexico, Australia, South Africa, and Ghana. Prior to joining GRC, Mr. Simidu was a Manager, Mine Planning at Worley, a global engineering company.	Multiple times in 2025; most recently from September 9 to 17, 2025.	1, 2, 4, 5, 12, 13, 15, 16, 17, 18, 19, 22, 23, 24 and 25
      Marcelo Zangrandi, MAIG (AMBA employee)
      Mr. Marcelo Zangrandi holds a Bachelor´s degree in Geology from Universidad Nacional de San Juan (1998) and a Graduate's degree in Geostatistical Evaluation of Ore Deposits from Universidad de Chile (2012). He is a member in good standing of the Australian Institute of Geoscientists (AIG). Mr. Zangrandi has over 30 years of practical experience in the mining industry and related research (geostatistics), mainly in exploration projects, open pit and underground mines, with gold, silver and copper, among other commodities. He is a senior geologist of AMBA Consultoria Ltda. ("AMBA"), a Brazilian consulting company. He has held various roles in geological exploration and mine operations, from the greenfield exploration to the resource estimation, mainly at Snowden Consulting (Brazil) and Barrick Gold (Argentina, Chile and Dominican Republic).	November 5 to 14, 2025	1, 8, 9, 11, 22, and 23
      Christian Laroche, P.Eng. (Synectiq employee)
      Mr. Christian Laroche graduated from Laval University with a degree in Metallurgical Engineering. He is registered at Ordre Ingénieur du Québec (OIQ). Mr. Laroche worked as a Process Engineer for BBA, as an engineering consultant and as Corporate Director of Metallurgy for Compagnie Minière Osisko. He spent 8 years as Director of Metallurgy at Osisko Gold Royalty and 3 years as Vice-President Metallurgy at Falco Resources. He was the GRC Technical Service Director of Metallurgy from 2022 to May 2024. He is currently a consulting metallurgist with Synectiq.	Most recently October 16 to 27, 2024	1, 10, 14, 22, and 23
      David Turner MAIG (GRC employee)
      Mr. David Turner graduated from Colorado State University, Fort Collins, Colorado where he earned his Bachelor of Science degree in Geology in 1992. He is a Member in good standing of the Australian Institute of Geoscientists (AIG) and a longstanding member of the Society of Economic Geologists (SEG). Mr. Turner has worked continuously for over 32 years in the exploration and mining industry, focused on precious and base metal exploration and development, on projects ranging from grassroots to advanced-stage exploration, and in operations at both underground and open pit mines in the USA, Mexico, El Salvador, Honduras, Nicaragua, Brazil and Bolivia for companies including BHP, Kinross, Yamana Gold, Mineros, Electrum Group and New Pacific Metals, amongst others. He is currently the Director of Geology for GRC.	November 3 to 14, 2025	1, 3, 5, 6, 7, 8, 9, 20, 21, 22, 23, and 24

      Technical data and information used in preparing this report also included documents from third-party contractors. The authors sourced information from referenced documents as cited in the text and listed in the References section of this report.

   3. Property Description, Location, and Ownership

      GRC holds a 100% interest in six properties that collectively comprise the Don David Gold Mine, including two production stage properties and four exploration stage properties, located in Oaxaca, Mexico, along the San Jose structural corridor. The Project is in the Sierra Madre Sur Mountains of southern Mexico, in the southwestern part of the State of Oaxaca. The Project is a significant precious and base metals epithermal deposit positioned along a major paved highway approximately 120 kilometers (km) southeast of Oaxaca City, the capital city of the State of Oaxaca. Because of their proximity and relatively integrated operations, we refer collectively to the six properties as the Don David Gold Mine. The two production stage properties are the only two of the six properties that make up the Don David Gold Mine that we consider to be independently material at this time. As of December 31, 2025, DDGM controlled twenty-nine mining concessions in Oaxaca State totaling 55,119 hectares and permits necessary to sustain mining operations. Expiration dates associated with the Project concessions range from August 30, 2049, to February 22, 2073.

      Table 0-1: Summary of DDGM Properties.

      DDGM PROJECTS	SEC STAGE	DEPOSITS	VEIN SYSTEMS
      Arista Project	Producing	Arista	Arista Switchback Three Sisters Gloria
      Alta Gracia Project	Producing	Alta Gracia	Mirador Independencia
      El Rey	Exploration
      Chamizo	Exploration
      Margaritas	Exploration
      Fuego	Exploration

      The Arista Project, a production stage property, has a relatively small surface infrastructure consisting of a processing plant made up of an 1,800 tonnes per day ("tpd") flotation plant, 250 tpd leaching plant, electrical power station (connected to the national electric power grid), water storage facilities, paste plant, filtration plant and dry stack facilities, stockpiles, and workshop facilities, all connected by sealed and unsealed roads. Additional structures located at the Project include offices, dining halls, a laboratory, core logging, and core storage warehouses. The tailings facilities are located approximately 500 meters (m) northeast of the flotation plant.

      DDGM must pay surface rights for concessions to the Mexican government to maintain its interest in the DDGM concessions. In 2025, DDGM satisfied these concessions' investment and assessment work requirements based on its work programs and past work completed. The annual concession tax paid for the mining concessions controlled by DDGM in 2025 was $1.28 million. DDGM concession payments are in good standing.

      DDGM has established surface rights agreements with several neighboring communities. The most significant agreement is with the San Pedro Totolapam Ejido, and the individuals impacted by current and proposed operations, which allow surface disturbance, where necessary, for DDGM's exploration activities and mining operations.

   4. History

      The Arista and Alta Gracia Projects are in the regional Tlacolula mining district in the State of Oaxaca, in south-west Mexico. According to the Mexican Geological Survey, the Servicio Geologico Mexicano ("SGM") mining activity was initiated in the early 1880s in the Tlacolula mining district, producing some 300,000 ounces of gold and silver from an ore shoot of the La Leona mine. However, no separate reported amounts of production were reported for each metal. SGM says that in 1892 two smelters were built and operated (Magdalena Teitipac and O'Kelly) near the village of Tlacolula for processing ores from the Alta Gracia, La Soledad, San Ignacio y Anexas, La Leona, La Victoria, and San Rafael silver mines. Subsequently, in 1911, Mr. Sken Sanders investigated the Totolapam mining region with a particular interest in the Margaritas mine. Most of these historical mines are within DDGM's mining concessions.

      While the DDGM Arista and Alta Gracia Projects are in the smaller mining subdistricts of San Jose de Gracia and Alta Gracia, respectively, only small-scale artisanal mining was historically conducted in these areas' subdistricts. No reliable production records exist for the historic production performed in the area.

      In 1998 and 1999, Arista Project concessions were leased to Apex Silver Corporation ("Apex"). Apex carried out an exploration program involving geologic mapping, surface sampling, and an eleven (11) hole reverse circulation (RC) drilling program comprised of 1,242 m into the flat-lying vein, manto-style deposit ("Manto vein").

      GRC has conducted continuous exploration since 2003, including extensive surface and underground drilling programs. Initial production at the Arista Project began from an open pit in 2010 and continued through 2011. Underground mining commenced in the Arista vein system in 2011, followed by the Switchback vein system in 2017 and the Three Sisters vein system in 2025. Underground production from the Arista, Switchback and Three Sisters systems continued in 2025.

      Since the commencement of production from the Don David Gold Mine in 2010, DDGM has produced 394,219 ounces of gold and 28,409,892 ounces of silver from the 6,620,105 tonnes shipped to the DDGM Processing Facility. In addition, 17,511 tonnes of copper, 73,457 tonnes of lead, and 201,692 tonnes of zinc have been produced from the plant.

   5. Geology Setting, Mineralization, and Deposit

      The DDGM Project area is predominantly comprised of volcanic rocks of presumed Miocene age, which overlay and intrude into basement rocks consisting of Cretaceous marine sediments. This district's gold and silver mineralization is related to a volcanogenic system and is considered epithermal in character. The DDGM Project mineralization occurs as structurally controlled epithermal deposits in veins and stockwork zones. It consists of concentrations of sulfides containing gold, silver, lead, copper, and zinc. Primary sulfide mineralization consists of pyrite, galena, sphalerite, chalcopyrite, and different minor amounts of argentite and silver sulfosalts. The mineralization is associated with gangue minerals such as quartz, calcite, and other minor elements.

      DDGM exploration efforts have primarily focused on the Arista Project mineral deposit, which includes the Manto vein, Arista, Switchback, and Three Sisters vein systems, and includes significant veins such as Arista, Baja, Soledad, Sandy's and Gloria, along with multiple ancillary structures. Historically, the principal hosts of mineralization have been the Arista and Switchback vein systems, known from drilling and underground workings in the Arista underground mine. More recently, exploration and underground development have also advanced the Three Sisters vein system. The Switchback deposit is approximately 500 m northeast of the Arista deposit, and the Three Sisters system is located immediately north of, and between the Switchback and Arista systems. All three vein systems are hosted in andesitic rocks, rhyolite dikes, and structural contacts with the basement sedimentary rocks. Mineralization in these systems is intermediate sulfidation with precious and base metals at economic grades. All three vein systems trend northwesterly, although locally vein orientations can range from north-south to east-west.

      The second zone of interest is the Alta Gracia Project, where low sulfidation epithermal, predominantly silver mineralized, veins are hosted in andesitic and rhyolitic rocks. This property has been investigated by drilling as well as surface and underground mapping of historical and recent workings. The Mirador and Independencia vein systems, which DDGM has mined, are one of several predominantly northeast trending vein systems on the property.

      Other mineralized zones and properties have been investigated, including preliminary drilling in areas such as Escondida, Chacal, and Salina Blanca on the Arista Project, as well as the Margaritas and El Rey properties. The Margaritas and El Rey properties host low sulfidation epithermal veins with volcanic associations.

   6. Exploration

      Don David Gold Mine properties include several mining sub-districts that had minimal exploration by modern methods before DDGM activity. DDGM acquired its Oaxaca mining concessions in 2003 and began exploring the Manto vein at the Arista Project, including drilling. Commencing in 2005, DDGM has carried out a continuous drilling program on other historical mine targets. The 2007 drill program included the discovery of the Arista vein and was the last RC drilling used. Since 2007, the continuous drilling programs have used wireline core drilling with 2.5 inches or 63.5-millimeter (mm) and 1.875 inches or 47.6 mm ("HQ" and "NQ") core diameters. Underground drilling began in 2011. In 2013, step-out drilling from underground stations in the Arista mine identified the first intersections of the Switchback vein system. By 2017, step-out drilling from underground stations in the Arista mine revealed the first intersections of what has now developed into the Three Sisters vein system. Drill programs have also targeted other zones of interest in the Arista mine, as well as epithermal vein systems in the Alta Gracia Project along with the Margaritas and El Rey properties. The Arista mine is located near the south-eastern limit of the 55 km long, northwest-trending San Jose structural corridor.

      DDGM continues an aggressive exploration program along the 55 km corridor that includes extensive surface and underground drilling and underground mine development. Mine development includes access ramps, drifts, and crosscuts to support drilling and underground access in the Arista, Switchback, and Three Sisters vein systems within the Arista mine area, and the Mirador and Independencia vein systems within the Alta Gracia mine area. Exploration techniques include airborne and ground

      geophysics, stream, soil and rock geochemical sampling, geologic mapping, petrographic and fluid inclusion studies, and drilling. These activities have identified multiple exploration targets, with recent work focused on the Arista and Alta Gracia zones due to proximity and ease of access to the DDGM processing facilities. Exploration drilling (core and RC) completed by DDGM through December 31, 2025 totals 2,158 drill holes for 523,937 m. The 2025 district exploration work program included 105 underground and six surface drill holes totaling 14,539 m of diamond drilling at a cost of $1.29 million. This total includes infill and grade-control drilling. Exploration mine development in 2025 totaled 485 m at a cost of $1.51 million. Other district surface exploration work totaled $1.86 million.

      The drill core is logged, sampled, and stored at the on-site exploration facilities within the DDGM operational site, using standard industry practices. All pulps, and selected coarse reject material, are recovered from an external laboratory and also stored in the DDGM exploration storage facilities.

      Since 2006, exploration samples have been analyzed by ALS Global ("ALS") at their ISO/IEC 17025:2017 and ISO 9001:2015 accredited laboratory in Vancouver, Canada. Initially, sample preparation was completed at ALS's Guadalajara laboratory in Mexico. In 2023, sample preparation was transferred to ALS's Santiago de Queretaro laboratory in Mexico, and since June 2024 sample preparation has been carried out at ALS's Hermosillo laboratory in Mexico.

      All exploration samples are subject to strict quality assurance and quality control ("QA/QC") protocols that include inserting certified reference materials (standards and blanks) and duplicate sampling. Mine channel samples and narrow diameter production core are assayed at the laboratory located at the DDGM processing facilities.

   7. Data Verification

      The DDGM staff follow stringent data storage and validation procedures and perform data verification continuously. The DDGM database manager last performed preliminary database validation in November 2025. The on-site database has a series of automated import, export, and validation tools to minimize potential errors. Any inconsistencies are corrected during the validation process before being handed over for final review and validation. The QPs visited the site in November 2025 to review data collection storage and undertake validation. The data verification procedures performed by the QPs involved the following:

      • Inspection of selected drill core to assess the nature of the mineralization and to confirm geological descriptions.

      • Inspection of geology and mineralization in underground workings of the Arista, Switchback and Three Sisters vein systems.

      • Verification that the collar coordinates coincide with underground workings or the topographic surface.

      • Verification that downhole survey bearing, and inclination values display consistency.

      • Evaluation of minimum and maximum grade values.

      • Investigation of minimum and maximum sample lengths.

      • Randomly selecting assay data from the databases and comparing the stored grades to the original assay certificates.

      • Assessing spelling or coding inconsistences (typographic and case sensitivity errors).

      • Ensuring full data entry and that a specific data type (collar, survey, lithology, and assay) is present.

      • Assessing sample gaps or overlaps.

   8. Mineral Processing and Metallurgical Testing

      Metallurgical testing completed by ALS in 2014, 2018, 2020 and 2022 supports the DDGM processing methodology. As exploration continues and additional mining areas are developed, additional metallurgical testing may be completed as needed to confirm metallurgical response for new ore types and domains. In addition, DDGM completed an October 2025 SEM-based mineralogical characterization of copper, lead, and zinc concentrate samples to support identification of the principal mineral carriers of payable metals and the occurrence of potential contaminants.

      Deleterious elements in the concentrate products are predominantly non-liberated sulfide and non-sulfide gangue, with cadmium and silica occurring within the zinc concentrate.

      During 2025, metallurgical recoveries at the DDGM processing facility for ore produced from the Arista mine averaged 71.5% for gold, 84.4% for silver, 62.3% for copper, 63.4% for lead, and 76.1% for zinc. Ore grades processed in 2025 were lower

      than those historically processed, and Three Sisters ore was processed for the first time in 2025. Based on metallurgical monitoring to date, metal recoveries have generally followed historical trends.

      The DDGM processing facility has a good body of metallurgical information comprising of historic test work supported by ALS studies. The metallurgical samples tested, and the ore presently treated in the plant, are considered representative of the material included in the life-of-mine ("LOM") plan with regards to grade and metallurgical response.

   9. Commodity Price Projections

      To estimate the Mineral Reserves and Mineral Resources in this report, the QP utilized prices based on conservative estimates ("Resource & Reserve Price Deck") of the average median consensus prices for each of the three years starting 2026 through 2028 as provided by Bloomberg's consensus commodity price forecast as at November 21, 2025. The median price was based on price estimates contributed by participating financial institutions (gold: $3,567 per ounce, silver: $40.80 per ounce, copper:

      $4.88 per pound, zinc: $1.26 per pound, lead: $0.95 per pound).

      Table 0-2: Mineral estimation Commodity Price Projections.

      Metal	Measure	Base Case	36-month average (as per Bloomberg Consensus)
      Au	$/oz	3,000	3,567
      Ag	$/oz	38.00	40.80
      Cu	$/lb	4.54	4.88
      Zn	$/lb	1.25	1.26
      Pb	$/lb	0.95	0.95

      For the Economic Analysis, the QP utilized the median consensus prices for each of the two years starting from 2026 through 2027 as provided by Bloomberg's consensus commodity price forecast as at February 17, 2026. The Economic Analysis provides for a remaining mine life of two years as based on current Mineral Reserves only. The Economic Analysis Price Deck is set forth in the below table:

      Table 0-3: Economic Analysis Commodity Price Projections.

      Metal	Measure	2026	2027	24-month average
      Au	$/oz	4,543	4,100	4,365
      Ag	$/oz	64.13	58.50	61.92
      Cu	$/lb	5.49	5.21	5.31
      Zn	$/lb	1.36	1.27	1.30
      Pb	$/lb	0.92	0.95	0.94

      The actual metal prices can change, either positively or negatively, from the assumptions above. If the assumed metal prices are not realized, this could have a negative impact on the operation's financial outcome. At the same time, higher than predicted metal prices could have a positive impact. Gold equivalencies are determined by taking the price for gold and silver and converting them to gold equivalent ratio for the respective remaining life of mine periods (average is 70.5 silver : 1 gold).

   10. Mineral Resources Estimates

       The modeling and estimation of Mineral Resources presented herein are based on technical data and information available as of December 31, 2025 (drilling database close November 1, 2025). DDGM models and estimates Mineral Resources from available technical details before generating Mineral Reserves.

       Marcelo Zangrandi, from AMBA Consultoria Ltda. ("AMBA"), completed the Mineral Resource estimate using Vulcan software. Wireframes for geology and mineralization were constructed by DDGM geology staff using Leapfrog Geo, based on underground mappings, assay results, lithological information from drill holes, and structural data. The model incorporates all significant vein systems identified to date: a total of 24 veins were interpreted and modelled for the Three Sisters system, 31 veins for the Switchback system, and 44 veins for the Arista system of the Arista mine; as well as 14 veins for the Independencia and Mirador systems of the Alta Gracia mine. Assays were composited to 1 m lengths and capped to various levels based on exploratory data analysis for each vein. For the Arista model, wireframes were filled with blocks of 10 m by 1 m by 10 m (x,y,z), which were sub-celled at wireframe boundaries (minimum sub-celling size 2.5 m by 0.5 m by 2.5 m (x,y,z). For the Three Sisters and Switchback models, the parent block size used was 5 m by 1 m by 10 m (x,y,z) and the minimum sub-cell size was 0.5 m by 0.5 m by 0.5 m (x,y,z) for Three Sisters and 2.5 m by 0.5 m by 2.5 m for Switchback. Block grades were interpolated using the ordinary kriging ("OK") interpolation algorithm. Block estimates were validated using industry-standard validation techniques. Classification of blocks used information distance-based criteria related to the spatial continuity of mineralization. Satisfying adequate minimum mining size continuity criteria and using a breakeven net smelter return ("NSR") cutoff grade of $150 per tonne for the Arista mine (Arista, Three Sisters and Switchback vein systems) and a gold equivalent ("AuEq") of 2.35 grams per tonne (g/t) for the Alta Gracia mine (See Section 12.7 for more discussion on cutoff grade).

       A summary of the Don David Gold Mine Mineral Resources, exclusive of Mineral Reserves, for the Arista mine, is shown in Table 0-4.

       	Tonnes	Grades					Cut-off grade
       Arista	(kt)	Au (g/t)	Ag (g/t)	Cu (%)	Pb (%)	Zn (%)	($/tonne)
       Measured mineral resources	3	1.4	192	0.32	1.04	4.22	150
       Indicated mineral resources	60	1.7	249	0.27	1.78	5.41	150
       Measured + Indicated mineral resources	63	1.7	246	0.28	1.74	5.35	150
       Inferred mineral resources	1,366	0.8	128	0.23	1.25	3.69	150

       Table 0-5 shows the Mineral Resources for the Alta Gracia mine. NSR cutoff values for the Mineral Resources were established using a zinc price of $1.25/pound (lb), a lead price of $0.95/lb, a copper price of $4.54/lb, a silver price of $38.00/ounce (oz) and a gold price of $3,000/oz.

       Mineral Resources have been classified under the definitions for Mineral Resources in S-K 1300, which are consistent with the Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Definition Standards for Mineral Resources and Mineral Reserves (CIM (2014) definitions).

       Table 0-4: Don David Gold Mine (Arista Mine) - Summary of Gold, Silver and Base Metal Mineral Resources, exclusive of Mineral Reserves at December 31, 2025.

       	Tonnes	Grades					Cut-off grade
       Arista	(kt)	Au (g/t)	Ag (g/t)	Cu (%)	Pb (%)	Zn (%)	($/tonne)
       Measured mineral resources	3	1.4	192	0.32	1.04	4.22	150
       Indicated mineral resources	60	1.7	249	0.27	1.78	5.41	150
       Measured + Indicated mineral resources	63	1.7	246	0.28	1.74	5.35	150
       Inferred mineral resources	1,366	0.8	128	0.23	1.25	3.69	150

       Table 0-5: Don David Gold Mine (Alta Gracia Mine) - Summary of Gold, Silver and Base Metal Mineral Resources, exclusive of Mineral Reserves at December 31, 2025.

       	Tonnes	Grades		Cut-off grade
       Altagracia	(kt)	Au (g/t)	Ag (g/t)	(AuEq g/t)
       Measured mineral resources	27	0.8	371	2.35
       Indicated mineral resources	141	0.5	270	2.35
       Measured + Indicated mineral resources	168	0.5	286	2.35
       Inferred mineral resources	148	0.6	296	2.35

       Notes on Mineral Resources:

       1. Mineral Resource estimated at December 31, 2025.

       2. The definitions for Mineral Resources in S-K 1300 were followed for Mineral Resources, which are consistent with CIM (2014) definitions.

       3. Metal prices used in the estimate were $3,000/oz Au, $38.00/oz Ag, $4.54/lb Cu, $0.95/lb Pb, and $1.25/lb Zn. See Section 1.9 for a discussion of the metal prices used.

       4. Mineral Resources are exclusive of Mineral Reserves.

       5. Mineral Resources that are not Mineral Reserves are materials of economic interest with reasonable prospects for economic extraction.

       6. Mining, processing, and overhead costs were based on 2025 actual costs for the Don David Gold Mine.

       7. An exchange rate of 19.5 Mexican Pesos ("MXP") to 1 U.S. dollar is applied to peso-denominated costs.

       8. Rounding of tonnes, average grades, and contained ounces may result in discrepancies with total rounded tonnes, average grades, and total contained ounces.

       9. Metallurgical recoveries are based on historical milling results and are 71.3% for Au, 85.0% for Ag, 58.9% for Cu, 65.8% for Pb, and 76.3% for Zn for Arista. For Altagracia, recoveries are 85.0% for Au and 72.0% for Ag.

   11. Mineral Reserves Estimates

       The Arista and Alta Gracia underground mine Mineral Reserve estimates follow standard industry practices, considering Measured and Indicated Mineral Resources. Only these categories have sufficient geological confidence to be considered Mineral Reserves. Subject to the application of modifying factors, Measured Resources may become Proven Reserves, and Indicated Resources may become Probable Reserves. Mineral Reserves are reconciled quarterly against production to validate dilution and recovery factors. The reserve estimate is based on technical data and information available as of December 31, 2025.

       Mineral Reserves are classified as Proven and Probable ("P&P"). Mine designs incorporate all modifying factors and must meet cutoff grade requirements to be considered feasible and economical for extraction.

       DDGM uses a breakeven NSR cutoff grade, considering actual metal prices, total mining, milling, general administration, smelting/refining costs, and plant recoveries for P&P Reserve estimations. The cutoff grade calculation does not include either exploration or capital costs, and the average operating costs used for reserve calculations are net of base metal credits and

       royalty payments. Plant recoveries used are the average of actual recoveries reported by the plant during the twelve months of 2025.

       The 2025 breakeven NSR cutoff grade for the Arista underground mine is based on a $150/t NSR. Gold, silver, copper, lead, and zinc metal price assumptions established in Section 1.9 were utilized to calculate the NSR value.

       The P&P Mineral Reserves for the Arista mine as of December 31, 2025, are summarized in Table 0-6.

       Table 0-6: Don David Gold Mine - Summary of Gold, Silver and Base Metal Mineral Reserves at December 31, 2025(1)(4).

       Description	Tonnes	Grades					Cut-off Grade	Metallurgical Recovery (%)
       Arista	(kt)	Au (g/t)	Ag (g/t)	Cu (%)	Pb (%)	Zn (%)	($/tonne)	Au	Ag	Cu	Pb	Zn
       Proven Mineral Reserves	26	1.9	476	0.22	0.81	1.90	150	71.3	85.0	58.9	65.8	76.3
       Probable Mineral Reserves	626	1.2	184	0.18	0.82	2.52	150	71.3	85.0	58.9	65.8	76.3
       Arista Mine Total	652	1.2	196	0.18	0.82	2.49

       Notes on Mineral Reserves in Tables 1-7:

       1. Metal prices used for P&P reserves were $3,000 per ounce of gold, $38.00 per ounce of silver, $4.54 per pound of copper, $0.95 per pound of lead and $1.25 per pound of zinc. See Section 1.9 for a discussion of metal prices used.

       2. A breakeven NSR cutoff grade of $150/t was used for estimations of P&P reserves at the Arista Underground Mine. The term "cut-off grade" means the lowest NSR value considered economic to process.

       3. Mining, processing, and overheads were based on 2025 actual costs for the Don David Gold Mine.

       4. P&P reserves are diluted and factored for expected mining recovery.

       5. An exchange rate of 19.5 Mexican Pesos ("MXP") to 1 U.S. dollar is applied to peso-denominated costs.

       6. Rounding of tonnes, average grades, and contained ounces may result in apparent discrepancies with total rounded tonnes, average grades, and total contained ounces.

   12. Mining Methods

       In 2010, DDGM began developing an underground mine to access the Arista and Baja veins, part of the Arista vein system. The Arista underground mine is approximately three kilometers from the DDGM processing facilities. In March 2011, DDGM began transitioning to processing the underground mineralization. Conventional drill and blast methods are currently used to extract ore from the Arista underground mine. Currently, DDGM uses long-hole open stopping ("LHOS") and Cut and Fill ("CAF").

       Since commercial production was declared at the Don David Gold Mine on July 1, 2010, through December 31, 2025, the plant has processed a total of 6,620,105 tonnes of open pit and underground ore to recover 394,219 ounces of gold and 28,409,892 ounces of silver.

       This Technical Report concludes that:

       • The mining methods being used are appropriate for the deposit being mined. The underground mine design, stockpiles, tailings facilities, and equipment fleet selection are appropriate for the operation.

       • The mine plan is based on historical mining and planning methods practiced at the operation for the previous years and presents a low risk.

       • Inferred Mineral Resources are not included in the mine plan and were sent to waste.

       • The mobile equipment fleet presented is based on the actual present-day mining operations, which is known to achieve the production targets set out in the LOM.

       • All mine infrastructure and supporting facilities meet the needs of the current mine plan and production rate.

       • Production from the Don David Gold Mine has proven that the Project has the grade and continuity required to justify continued development and mining. The known veins and other Don David Gold Mine targets are underexplored by drilling. If DDGM maintains its exploration programs, excellent potential exists for reserves to maintain or grow.

   13. Processing and Recovery Methods

       During 2009 and 2010, DDGM constructed a processing plant and infrastructure at the Arista mine. The processing plant has a differential flotation section capable of processing polymetallic ores and producing up to three separate concentrate products for sale and an agitated leach circuit capable of producing gold and silver doré for purchase. The DDGM mill's flotation circuit has undergone modifications in the circuit, higher capacity pumps and extra floatation cells that increased name plate capacity to 2,000 tpd (1,800 sulfides and 200 oxides). There is no indication that the characteristics of the material planned for mining will change, and therefore the recovery assumptions applied for future mining are considered reasonable for the LOM.

   14. Project Infrastructure

       All material mine and process infrastructure and supporting facilities are included in the current general layout to ensure that they meet the needs of the mine plan and production rate and notes that:

       • The Don David Gold Mine is 114 km, or two hours by road from Oaxaca City, the main service center for the operation, with good year-round access.

       • A flotation tailings impoundment was constructed in a valley just below the process plant site. The impoundment is double lined with the first liner made of clay and synthetic material that acts as a leak prevention system with an effective absorption equal to approximately 3 m of clay. The second liner is 1.5 mm Linear Low-Density Polyethylene ("LLDPE"), a permitting requirement. The method of subsequent embankment construction to obtain total capacity was downstream.

       • Construction of a filtration plant and dry stack facility commenced in September 2020 and was commissioned in March 2022. The filtration plant and existing paste plant (commissioned in October 2019) handle 100% of current reserves tailings production.

       • Up until 2018, the site was powered by diesel generators. In 2019, DDGM successfully connected a power line to its Arista Project from the Mexican Federal Electricity Commission's (Comisión Federal de Electricidad or CFE) power grid. Before this connection, the DDGM project operated 100% from electricity generated from more expensive and higher emission diesel fuel. In 2021, there was an increase in power consumption due to ventilation and dewatering pumps requiring the installation of capacitors that improved and stabilized the power supply. In 2021, DDGM also initiated conversations with CFE to expand further the load delivered to stabilize the energy supply.

       • Water requirements to process ore are primarily sourced from water pumped to the surface from the underground dewatering system. Water in the tailings facility is recycled to the DDGM processing plant, and the excess water pumped from the underground workings is discharged at the surface into decantation ponds. DDGM has the necessary permits to discharge underground mine water at the surface. Water sampling from rivers and creeks is conducted regularly and sent to an external laboratory for analysis.

       • All process buildings and offices for operating the mine have been constructed. Camp facilities in San Jose de Gracia were built with recycled materials.

   15. Market Studies and Contracts

       Since the operation commenced commercial production in July 2010, a corporate decision was made to sell the concentrate on the open market. All commercial terms entered into between the buyer and DDGM are confidential but are considered within standard industry norms.

       The information provided by GRC on marketing, contracts, metal price projections, and exchange rate forecasts is consistent with the information publicly available and within industry norms.

   16. Environmental Studies, Permitting and Plans, Negotiations, or Agreements with Local Individuals or Groups

       In connection with mining, milling, and exploration activities, DDGM is subject to all Mexican federal, state, and local laws and regulations governing the protection of the environment. Laws and regulations include the protection of air and water quality, hazardous waste management, mine reclamation and protection of endangered or threatened species. Additional areas of environmental consideration for mining companies (including DDGM) include, but are not limited to, acid rock drainage, cyanide containment and handling, contamination of water sources, dust, and noise.

       All mining and environmental activities in México are regulated by the Dirección General de Minas ("DGM") and by the Secretaría de Medio Ambiente y Recursos Naturales ("SEMARNAT") from México City, under the corresponding laws and regulations. The environmental impact and risk relating to atmosphere emissions and hazardous waste produced and treated operate under a unique environmental license ("Licencia Ambiental Unica" or "LAU"). This environmental license is issued after approval by the Evaluación del Impacto Ambiental ("EIA"). Special permits are also required for new developments such as expansions, tailings dams, etc. DDGM must also obtain various permits for surface and underground water use including waste-water discharge. The permissions are granted by the Comisión Nacional del Agua ("CONAGUA"), the administrative, technical advisory commission of SEMARNAT. CONAGUA administers national waters, manages and controls the country's hydrological system, and promotes social development.

       DDGM is required to prepare a mine closure plan for the possible future abandonment of the Arista and Alta Gracia Mines. WSP Grupo Mexico S.A. de C.V. ("WSP") has prepared a mine closure plan and reclamation budgets. The total estimated closure and reclamation cost for the Arista and Alta Gracia Mines, according to the information provided in 2025, amounts to

       $14.5 million (excluding taxes). This amount was calculated with the assumptions of the technical information available during the assessment.

   17. Capital and Operating Costs

       The support for capital and operating costs is based on realized costs, quotations, and estimates in 2025 dollars. The estimated capital expenditures, excluding mine closure costs and operating costs, are to a feasibility level of accuracy (15%) and excludes a contingency estimate due to two-year remaining life of mine, as based on Mineral Reserves only. The mine closure costs include a contingency range of 10% to 15% for each component in the closure plan, with an average of 10% applied between the Arista and Alta Gracia projects. No inflation factors or changes to exchange rates have been used in the economic projections.

       Total Don David Gold Mine life of mine ("LOM") capital expenditures, including mine closure costs, are estimated to be $39.6 million, and excludes any contingency as applied to sustaining capital expenditures costs and includes an average of 10% contingency as applied to mine closure costs.

       Operating costs are estimated based on an evaluation of actual historical and current expenditure for labor, consumables, and established DDGM contracts. The operating costs have a fixed and variable component and are estimated at $247/t and exclude any contingency estimate. The total operating costs are based on applying the estimated unit costs to the estimated total ore tonnes of 0.7 million tonnes to be processed over the two-year remaining LOM.

       The capital and operating costs estimated for the Don David Gold Mine are reasonable based on industry-standard practices and actual costs observed for 2025.

   18. Economic Analysis

       The Don David Gold Mine has a two-year LOM given the Mineral Reserves as described in this Report. Assumptions underlying the determination of Free Cash Flow and Net Present Value ("NPV") include:

       • Capital and operating costs as summarized above and in Section 1.17 and below in Section 18. Of note, mine closure costs of $14.8 million are included in the Economic Analysis, which consists of the Arista, Alta Gracia and other nearby project areas.

       • Metals prices over the remaining LOM are based on the Economic Analysis Price Deck summarized above in Section 1.9 and below in Section 16.

       • No inflation factors have been used in economic projections; however, no contingency estimate has been applied to sustaining capital expenditures and operating costs, and an average of 10% contingency has been applied to mine closure costs only and a 5% discount rate applied for NPV.

       • An exchange rate of 18.5 Mexican Pesos ("MXP") exchange rate to 1 U.S. dollar is applied to peso-denominated costs, which is a conservative estimate to the approximate spot price as at November 21, 2025.

       • Revenues are estimates based on the Economic Analysis Price Deck mentioned earlier and the terms established in the doré and concentrate contracts discussed in Section 16.

       • Only material in the Reserves has been considered in the life of mine plan.

       • Optimized mine that assumes full depletion of the Arista Reserves through 2027.

       Based on Mineral Reserves only, the free cash flow is estimated at $74.8 million, and the NPV is estimated at $71.7 million.

   19. Interpretations and Conclusions

       This Technical Report represents the most reasonable interpretation of the available Mineral Resource and Mineral Reserve as of the effective date. The conversion of Mineral Resources to Mineral Reserves was undertaken using industry-recognized methods and estimated operational costs, capital costs, and plant performance data. Likewise, the processing facilities and related infrastructure are appropriately designed to convert the minerals into a saleable product. Thus, it is considered to be representative of future operating conditions. This Technical Report has been prepared with the latest environmental and closure cost requirements. DDGM has obtained, or is in the process of applying for, the required Environmental Impact Studies and permits to continue operating in accordance with Mexican Laws and Regulations.

   20. Recommendations

       Recommendations for the next phase of work have been broken into those related to ongoing exploration activities and those related to additional technical studies focused on operational improvements. A detailed list of recommendations is described in the "Recommendations" section. Recommended work programs are independent and can be conducted concurrently unless otherwise stated.

2. INTRODUCTION
   1. Report Purpose

      This Technical Report was prepared for Gold Resource Corporation ("GRC") as a Technical Report in accordance with SEC S-K 1300 for the Don David Gold Mine, a wholly owned subsidiary of GRC. DDGM is an underground gold, silver, and base-metal production and exploration stage project in Oaxaca, Mexico.

      The report contains estimates of Mineral Reserves and Mineral Resources for the Project, effective as of December 31, 2025, prepared following S-K 1300 guidelines. These estimates supersede and replace the corresponding Mineral Reserve and Mineral Resource estimates for the Project contained in the DDGM Technical Report in accordance with SEC S-K 1300 and disclosed in the GRC Form 10-K for the year ended December 31, 2024. The quality of information, conclusions, and estimates presented in this report are consistent with the level of effort by the QPs, based on:

      1. The information available at the time of preparation;

      2. Data supplied by outside sources; and

      3. The assumptions, conditions, and qualifications outlined in this Technical Report.

   2. Qualified Persons

      A Qualified Person ("QP"), as defined in Regulation S-K Subpart 1300, is a mineral industry professional with at least five years of relevant experience related to the type of mineralization and deposit type represented at DDGM, and who is an eligible member or licensee in good standing of a recognized professional organization. The QPs responsible for this Technical Report are specialists in geology and exploration; mineral resource and mineral reserve estimation and classification; underground and surface mining; geotechnical; environmental and permitting; metallurgical testing and mineral processing (including process design); capital and operating cost estimation; and mineral economics. See Section 1.2 for additional details regarding the QPs

      for this Technical Report. Technical data and information used in the preparation of this Technical Report include information and documents prepared by third-party contractors. The QPs have relied upon referenced documents as cited in the text and listed in Section 24, "References".

   3. Effective Date

      The effective date of this Report is December 31, 2025.

   4. Previous Technical Reports

      DDGM has previously filed technical reports on the Don David Gold Mine, listed in chronological order:

      • Lopez, Noble, Jaacks, 2012. NI 43-101 Technical Report for Mineral Resources for the El Arista project, Oaxaca State, Mexico, prepared by Pincock, Allen & Holt, effective date July 10, 2012

      • Devlin & Alvarado, 2013. Report on the Reserve Estimate for the La Arista Underground Mine at the El Arista project, Oaxaca, Mexico, prepared by Gold Resource Corp., effective date October 1, 2013

      • Devlin & Alvarado, 2014. Report on the Reserve Estimate for the La Arista Underground Mine at the El Arista project, Oaxaca, Mexico, prepared by Gold Resource Corp., effective date December 1, 2013

      • Devlin, 2015. Report on Estimates of Reserves and Measured and Indicated Mineralized Material at the El Arista project, Oaxaca, Mexico, prepared by Gold Resource Corp., effective date December 31, 2014

      • Devlin, 2016. Report on Estimates of Reserves and Mineralized Material at the Arista project, Oaxaca, Mexico, prepared by Gold Resource Corp., effective date December 31, 2015

      • Devlin, 2017. Report on Estimates of Reserves and Mineralized Material at the Oaxaca Mining Unit, Oaxaca, Mexico, prepared by Gold Resource Corp., effective date December 31, 2016

      • Brown & Devlin, 2018. Report on Estimates of Reserves and Mineralized Material at the Oaxaca Mining Unit, Oaxaca, Mexico, prepared by Gold Resource Corp., effective date December 31, 2017

      • Brown, Garcia, Devlin & Lester, 2019. Report on the Estimate of Mineral Resources and Mineral Reserves for the Oaxaca Mining Unit, Oaxaca, Mexico, prepared by Gold Resource Corp., effective date December 31, 2018

      • Brown, Garcia, Devlin & Lester, 2020. Report on the Estimate of Mineral Resources and Mineral Reserves for the Oaxaca Mining Unit, Oaxaca, Mexico, prepared by Gold Resource Corp., effective date December 31, 2019

      • Brown, Garcia & Devlin, 2021. Report on the Estimates of Mineral Resources and Mineral Reserves for the Don David Mine, Oaxaca, Mexico, prepared by Gold Resource Corp., effective date December 31, 2020

      • Brown, Garcia, Zangrandi, Lachapelle & Reyes 2021. NI 43-101 Technical Report for Mineral Resources, Oaxaca State, Mexico, prepared by Gold Resource Corp., effective date December 31, 2020

      • Simidu, Zangrandi & Lachapelle 2022. S-K 1300 Technical Report for Mineral Resources, Oaxaca State, Mexico, prepared by Gold Resource Corp., effective date December 31, 2021

      • Simidu, Zangrandi, Frenette & Laroche 2023. S-K 1300 Technical Report for Mineral Resources, Oaxaca State, Mexico, prepared by Gold Resource Corp., effective date December 31, 2022

      • Simidu, Zangrandi, Turner, Frenette & Laroche 2024. S-K 1300 Technical Report for Mineral Resources, Oaxaca State, Mexico, prepared by Gold Resource Corp., effective date December 31, 2023

      • Simidu, Zangrandi, Turner & Laroche 2025. S-K 1300 Technical Report for Mineral Resources, Oaxaca State, Mexico, prepared by Gold Resource Corp., effective date December 31, 2024

   5. Information Sources and References

      The primary information source referenced in this Report is the 2024 Technical Report:

      • Simidu, Zangrandi, Turner, Frenette & Laroche 2025. S-K 1300 Technical Report for Mineral Resources, Oaxaca State, Mexico, prepared by Gold Resource Corp., effective date December 31, 2024

      The QPs also used the other reports and documents noted in Section 24, "References", in preparing this report.

      The metric system for weights and units has been used throughout this report. Mass is reported in metric tons ("tonnes or t") consisting of 1,000 kilograms per tonne. Gold and silver are reported as grams per tonne ("g/t"). Copper, lead, and zinc are reported as percentages ("%").

      Gold and silver ounces are reported in troy ounces converted using 31.1035 grams per troy ounce. Unless otherwise stated, all currency is in U.S. dollars ("$").

3. PROPERTY DESCRIPTION AND LOCATION

   The Project is comprised of six properties. The Arista and Alta Gracia Projects are located in southern Mexico's Sierra Madre del Sur Mountains, in the central part of the State of Oaxaca (Figure 0-1). The Projects are along a paved highway approximately 90 to 120 km southeast of the capital city of Oaxaca. Oaxaca has daily passenger airline service to Mexico City, Guadalajara, Los Angeles, California and Houston, Texas, USA serviced by Xoxocotlan International airport. The approximate center of the Project area is N16.68°, W96.17° (Figure 0-1). The El Rey, Chamizo, Margaritas and Fuego properties are exploration-stage properties within the Project.

   
   
   Figure 0-1: General Location of the six Properties Comprising the Don David Mine.
   1. Mineral Tenure

      DDGM currently holds an interest in twenty-nine (29) mining concessions in Oaxaca State totaling 55,119 hectares (Table 0-7, Figure 0-2). Expiration dates associated with the Don David Mine mining concessions range from August 30, 2049 to February 22, 2073.

      Table 0-7: Mining Concessions Owned by Don David Gold Mexico, S.A. de C.V.

      Number	Concession Name	Title Number	Hectares	Term of Mining Concession
      				From	To
      1	MINA DEL AIRE	158272	72.00	2/23/1973	2/22/2073
      2	EL AGUILA	222844	899.06	9/9/2004	9/8/2054
      3	LA TEHUANA	210029	925.00	8/31/1999	8/30/2049
      4	EL CHACAL	232628	375.00	9/26/2008	9/25/2058
      5	EL PILON	232629	1,070.35	9/26/2008	9/25/2058
      6	PITAYO FRACCIÓN 1	231124	429.63	1/17/2008	1/16/2058
      7	PITAYO FRACCIÓN 2	231125	22.05	1/17/2008	1/16/2058
      8	PITAYO FRACCIÓN 3	231126	113.31	1/17/2008	1/16/2058
      9	PITAYO FRACCIÓN 4	231127	2.82	1/17/2008	1/16/2058
      10	EL TALAJE	231128	1,015.95	1/17/2008	1/16/2058
      11	LA HERRADURA	231129	3,628.85	1/17/2008	1/16/2058
      12	DAVID FRACCIÓN 1	232851	625.59	10/30/2008	10/29/2052
      13	DAVID FRACCIÓN 2	232852	920.76	10/30/2008	10/29/2052
      14	SAN LUIS	246866	2,820.07	12/12/2008	12/11/2052
      15	EL COYOTE	246864	2,799.55	3/12/2010	2/11/2060
      16	EL ZORRITO	246922	8,836.42	11/12/2009	11/11/2059
      17	LA CURVA	246825	1,940.28	3/12/2010	2/11/2060
      18	EL CHAMIZO	246865	17,897.54	9/23/2011	9/22/2061
      19	ZOPI	246934	504.00	11/8/2011	11/7/2061
      20	LA REYNA	225401	692.00	8/31/2005	8/30/2055
      21	EL REY	225373	172.00	8/26/2005	8/25/2055
      22	EL VIRREY	226269	36.00	12/2/2005	12/1/2055
      23	EL MARQUEZ	246863	1,434.89	6/5/2009	6/4/2059
      24	SAN MIGUEL FRACCIÓN 2	241818	1,122.84	3/27/2013	3/26/2063
      25	SAN PEDRO FRACCIÓN 1	233694	2,554.00	3/30/2009	2/23/2054
      26	SAN PEDRO FRACCIÓN 2	233693	1,860.21	3/30/2009	2/23/2054
      27	EL AGUILA III	246842	2,250.00	12/16/2013	12/16/2063
      28	CORRECAMINOS	246834	97.81	8/25/2015	8/24/2065
      29	TLACUACHE	245147	1.04	11/8/2016	11/7/2066
      TOTAL			55,119.02

      Figure 0-2: Don David Mine Concessions (concession numbers are listed in Table 3-1).
      
      

      Mineral rights in Mexico belong to the Mexican federal government and are administered according to Article 27 of the Mexican Constitution. Concessions grant the right to explore and exploit all minerals found in the ground. All mining concessions comprising the Don David Gold Mine are exploitation concessions, which may be granted or transferred to Mexican citizens and corporations. Mexican subsidiaries of GRC hold the leases or concessions. Exploitation concessions have a term of 50 years and can be renewed for another 50 years. Maintenance of concessions requires the semi-annual payment of mining duties (due in January and July) and the submission of confirmation of work reports on a calendar year basis. The confirmation of work reports are required to be filed in May for the preceding calendar year. The number of mining duties and annual assessment are set by regulation and may increase over the life of the concession and include periodic adjustments for inflation. Mining concessions are registered at the Public Registry of Mining in Mexico City and regional offices in Mexico.

      Mexican mining law does not require payment of finder's fees or royalties to the government, except for a discovery premium connected with national mineral reserves, concessions, and claims or allotments contracted directly from the Mexican Geological Survey. None of the claims held by GRC's subsidiaries are under any such discovery premium regime.

      DDGM is required to pay concession surface fees to the Mexican government twice annually (January and July), calculated based on the number of hectares held, to maintain its mining concessions in good standing. In 2025, the total concession surface fees paid for the mining concessions controlled by DDGM was $1.28 million, and all payments were current as of December 31, 2025.

      In 2025, DDGM satisfied the investment and assessment of work requirements based on its annual work programs and past work completed. DDGM concession payments are in good standing.

      Table 0-8: Don David Gold Mine Concession Maintenance Fees by Property.

      		TOTAL NUMBER OF CONCESSIONS		TOTAL SIZE		ACQUISITION DATE RANGE		2025 MAINTENANCE FEES PAID
      			(in hectares) *
      Production Stage Properties:
      Arista		18		24,372		2002 to 2016		$	565,498
      Alta Gracia		3		5,175		2008			118,503
      Subtotal				29,547				$	684,001
      Exploration Stage Properties:
      Rey		4		2,335		2002 to 2009		$	54,167
      Chamizo		2		19,758		2011 to 2013			462,078
      Margaritas		1		925		2002			21,181
      Fuego		1		2,554		2013			59,731
      Subtotal				25,572					597,157
      Total:		29		55,119				$	1,281,158

      In 2013, the Mexican federal government enacted a tax reform package effective January 1, 2014. The reform introduced several significant changes. The planned corporate income tax rate reductions (29% in 2014 and 28% thereafter) were repealed, and the corporate tax rate remains at 30%. The tax base for income tax was broadened, with certain limitations placed on deductions. The business flat tax ("IETU"), which had been effective from 2008 to 2013, was repealed in 2014. A special mining royalty tax of 7.5% was applied to net profits of a property concession holder derived from the sale or transfer of extraction-related activities. Net profits for this royalty are determined using the general taxable income calculation, with exceptions for deductions related to investments in fixed assets and interest. Effective 2021, deductions for amounts paid for surface rights related to mining concessions were no longer allowed. In addition, owners of mining concessions are required to pay an additional 0.5% extraordinary royalty fee on gross revenue derived from the sale of gold, silver, and/or platinum. Starting in 2025 and going forward, the Mexican federal government increased the special mining royalty tax from 7.5% to 8.5%, and the extraordinary royalty fee was increased from 0.5% to 1.0%. A further 10% withholding tax on dividend distributions was also introduced. However, the tax treaty between the United States and Mexico to avoid double taxation reduces this withholding tax up to 5%. The Company has determined that it qualifies for an exemption or a 0% Mexico Dividend withholding rate through the US-Mexico tax treaty as the beneficial owner owns at least 80% of the voting shares.

   2. Surface Rights

      In this Technical Report, all mining concessions containing Mineral Resources and Mineral Reserves are controlled by DDGM. Further, DDGM has secured and maintained the necessary permits for the Don David Gold Mine's exploration, development, and production.

   3. Royalties

      On October 14, 2002, DDGM leased its first three mining concessions from a former consultant to the company. These concessions are El Aguila, Mina Del Aire, and La Tehuana, totaling approximately 1,896 hectares. The El Aguila and Mina Del Aire concessions are now part of DDGM's Arista mine, and the La Tehuana concession comprises the Margaritas property.

      The initial lease agreement with the former consultant was subject to a 4% net smelter return royalty where production is sold in the form of gold/silver doré and 5% for production sold in concentrate form. These royalty terms were renegotiated with a new agreement signed on November 9, 2023, reducing the net smelter return royalty for producing gold/silver doré and production sold in concentrate form to 3%. Subject to meeting minimum exploration requirements, the lease has no expiration term. DDGM may terminate the lease at any time upon written notice to the lessor, and the lessor may terminate it if DDGM fails to fulfill any of its obligations, primarily of paying the appropriate royalty to the lessor.

      In 2010, DDGM subsequently acquired, at no additional cost, two additional concessions from the former consultant: El Chacal and El Pilon, totaling approximately 1,445 hectares, each is subject to a 2% royalty to the consultant but is not subject to the lease.

      DDGM has since filed for and received additional concessions for the Project that total approximately 45,029 hectares referred to as: El Pitayo Fracción 1 to 4, El Talaje, El Coyote, El Zorrito, San Luis, La Curva, La Herradura, David Fracción 1 and 2, El Chamizo, Zopi, San Miguel Fracción 2, El Aguila III, Correcaminos and Tlacuache. These additional concessions are not part of the concessions leased or acquired from DDGM's former consultant.

      The Don David Gold Mine also includes the El Rey property, which adjoins DDGM's El Chamizo concession on the west side. These concessions are El Rey, El Virrey, La Reyna, and El Márquez. DDGM acquired the El Virrey concession from the former consultant, and it is subject to a 2% net smelter return royalty payable to the consultant. DDGM obtained the remaining concessions by staking claims and filing for concessions with the Mexican government. These concessions total approximately 2,335 hectares.

      In March 2013, DDGM acquired the San Pedro Fracción 1 and San Pedro Fracción 2 concessions from Almaden Minerals Ltd. ("Almaden"), subject to a 2% net smelter return royalty. The San Pedro Fracción 1 concession consists of 2,554 hectares and is located south of DDGM's Alta Gracia and El Chamizo properties. The San Pedro Fracción 2 concession consists of approximately 1,860 hectares and is surrounded by DDGM's El Chamizo concession and is included as part of the El Chamizo property. Any future production from the San Pedro Fracción 1 and San Pedro Fracción 2 concession is subject to Almaden's 2% net smelter return royalty.

   4. Environmental Aspects
      1. Mine Closure

         DDGM is required to prepare a mine closure plan for the possible future abandonment of the Arista and Alta Gracia Projects. WSP has prepared a Mine Closure Plan and Reclamation Budgets for the Arista mine. The closure cost estimate includes funds covering the tailings ponds, waste rock stockpiles ("tepetateras"), and securing and cleaning up the other surface and underground mine facilities. The total estimated closure and reclamation cost for the Arista and Alta Gracia Mines is estimated to be $14.5 million. WSP prepared its report in December 2025.

         See Section 17, "Environmental Studies, Permitting and Social or Community Impact" for additional information on the environmental regulation of the Project.

   5. Permits

      DDGM has obtained, or is in the process of applying for, the required environmental impact assessments and permits necessary to continue operating in accordance with Mexican Laws and Regulations.

   6. Other Significant Factors and Risks

      We are not aware of other significant factors and risks that may affect access, title or right, or ability to perform work at the mine.

   7. Comment on Section 3

      In the opinion of the QPs:

      • GRC was provided with a legal opinion that supported that the mining concessions held by DDGM for the Don David Gold Mine are valid and that GRC has a legal right to mine the deposit.

      • GRC was provided with a legal opinion that supported that the surface rights held by DDGM for the Don David Gold Mine are in good standing. The surface rights are sufficient in the area for the mining operation infrastructure and tailings facilities.

      • GRC received a legal opinion outlining royalties payable for the concessions held by DDGM.

      • The information discussed in this section supports the declaration of Mineral Resources, Mineral Reserves and the development of a mine plan with accompanying financial analysis.

4. ACCESSIBILITY, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND PHYSIOGRAPHY
   1. Access

      DDGM's primary operations are located near the village of San José de Gracia, within the Municipality of San Pedro Totolapam. The Municipality of San Pedro Totolapam is located in the Region of the Central Valleys, 89 km southeast of Oaxaca City, and is part of the District of Tlacolula. Access to the Project area from Oaxaca City is via the paved federal Highway 190, which passes through the village of San José de Gracia.

      The Don David Gold Mine is approximately 4 km northwest of the village of San José de Gracia. Gravel and paved roads have been constructed from the village to the mine and mill sites, supporting adequate property access by small and large vehicles.

      The Alta Gracia Project is approximately 20 km northeast of San Pedro Totolapam, the seat of the municipal government. The Project is accessible by a gravel road that departs the paved highway approximately 13 km east of San Pedro Totolapam. The haulage distance by road from Alta Gracia to the DDGM Processing Facility, where the ore is processed, is about 32 km.

   2. Climate

      The climate of the DDGM area is temperate, semi-dry, and warm to hot. Most rainfall occurs in the summer months (June -August), and the annual average precipitation in the Project area is approximately 400 mm, with significant fluctuations occurring. The recent average yearly temperature on the mine site is 22 degrees centigrade (°C); measurements at the Totolapam station from 1975 to 2008 showed an annual average of 24.2°C. Minimum yearly temperatures generally occur in January, while maximum temperatures typically occur in March through May; the yearly temperature range is generally between 9°C and 33°C. Mining operations are conducted on a year-round basis.

   3. Topography, Elevation, And Vegetation

      The Don David Gold Mine is in the state of Oaxaca in southern Mexico, which is bordered by the states of Puebla, Veracruz, Chiapas, and Guerrero, with the Pacific Ocean to the south. The DDGM Project areas are in the physiographic sub-province of Tierras Altas de Oaxaca, part of the Sierra Madre del Sur physiographic province, in the south-western part of Mexico.

      Oaxaca has one of the most rugged terrains in Mexico, with mountain ranges that abruptly transition into the sea. Oaxaca has several mountain chains with elevations varying from sea level to more than 3,700 meters above sea level (masl). Between these mountains are primarily narrow valleys, canyons, and ravines. The mountains are formed mainly by the convergence of the Sierra Madre del Sur, Sierra Madre de Oaxaca and Sierra Atravesada into what is referred to as the Oaxaca Complex (Complejo Oaxaqueño).

      The Arista and Alta Gracia Projects of the Don David Gold Mine are located within the municipality of San Pedro Totolapam. The municipality's surface is irrigated by the Rio Grande River, with many tributary rivers also irrigating other project areas. The majority of watercourses (arroyos) are dry throughout most of the year. Elevations range from 660 to 2,480 masl in GRC's Project areas with somewhat lower elevations found in the Arista and Alta Gracia Projects (up to 1,680 masl). The area is rugged with generally steep slopes (up to 30°) although more vertical cliffs are also present. The area is very rocky with thorn bushes and stunted deciduous temperate vegetation typical of dry savannah climates. Locally, cacti, both columnar and candlestick types, are a prominent vegetation feature. Subsistence farming occurs in the area, and the main agricultural crop is agave cacti, which are cultivated to produce mezcal.

   4. Infrastructure

      The current general layout includes all mine, process infrastructure, and supporting facilities to ensure that they meet the needs of the mine plan and production rate.

      The Don David Gold Mine is 114 km, or two hours by road from Oaxaca City, the main service center for the operation, with good year-round access. A workforce familiar with mining and the necessary support facilities is present in the region. The company provides transportation to and from their local home bases. The village of San Jose de Gracia supplies some of the crew for the mine, while other workers come from Oaxaca City or other nearby villages.

      The processing plant has a differential flotation circuit capable of processing polymetallic ores and producing up to three separate concentrate products for sale and an agitated leach circuit capable of producing gold and silver doré for purchase. The DDGM mill flotation circuit and agitated leach processing capacities provide for a nominal 2,000 tpd.

      A flotation tailings impoundment was constructed in a valley just below the process plant site.

      The impoundment is double lined with the first liner made of clay and synthetic material that acts as a leak prevention system with an effective absorption equal to approximately three meters of clay.

      The second liner is a welded High-Density Polyethylene (HDPE), which was a permitting requirement. The method of subsequent embankment construction to obtain total capacity was upstream.

      Construction of a filtration plant and dry stack facility commenced in September 2020 and was completed in early 2022. The filtration plant and existing paste plant (commissioned in October 2019) handle 100% of current tailings production.

      DDGM has several permitted waste-rock disposal areas at the Arista and Alta Gracia Projects. These waste disposal areas were designed mainly as valley fill sites.

      Up until 2018, diesel generators mainly provided power at the site. In 2019, DDGM successfully connected a power line to its Arista mine from the Mexican Federal Electricity Commission's (Comisión Federal de Electricidad or "CFE") power grid. Before this connection, the Project operated 100% from electricity generated from more expensive, higher-emission diesel fuel. The mine and plant can remain operational using the diesel generators maintained for backup use. In 2021, there was an increase in power consumption due to ventilation and dewatering pumps requiring the installation of capacitors that improved and stabilized the power supply. In 2021, DDGM also initiated conversations with CFE to expand the load delivered to stabilize the energy supply. In 2022, the capacitors were installed and commissioned, and CFE expanded the load delivered to attend to the higher demand on site.

      Water requirements to process ore are primarily sourced from water pumped to the surface from the underground mine dewatering system. Previously, some water was sourced from the local river for which payment was made to the National Water Commission (Comisión Nacional del Agua, or "CONAGUA"); however, this consumption is now minimal, and river water is only used for the camp facilities. DDGM has the necessary permits to discharge underground mine water at the surface. Water in the tailings facility is recycled to the DDGM processing plant, and the excess water pumped from the underground workings is discharged at the surface into decantation ponds. Water sampling from rivers and creeks is conducted regularly and sent to an external laboratory for analysis.

      All process buildings and offices for operating the mine have been constructed. Camp facilities are in the village of San Jose de Gracia.

      Plan drawings and more detailed information regarding the property infrastructure are provided in the Project Infrastructure section of this report.

   5. Sufficiency of Surface Rights

      This report's mineral resources and mineral reserves are located on mining concessions controlled by DDGM. The mine's processing facility and supporting infrastructure are within the area of surface rights and mineral tenure owned by the Don David Gold Mine.

   6. Comment on Section 4

      It is the opinion of the QPs that there are sufficient mineral tenure and surface rights to support the LOM mining operations due to the following:

      1. The existing and future infrastructure (planned filtration plant and dry stack tailings facility).

      2. Availability of staff.

      3. Current power, water, and communications facilities.

      4. Transportation methods.

      5. Planned modifications and supporting studies are well-established.

5. HISTORY
   1. Ownership History

      The Arista and Alta Gracia Projects are in the regional Tlacolula mining district in the state of Oaxaca, in south-west Mexico. According to the Mexican Geological Survey, the Servicio Geologico Mexicano ("SGM") mining activity was initiated in the early 1880s in the Tlacolula mining district, producing some 300,000 ounces of gold and silver from an ore shoot in the La Leona mine. However, no separate amounts of production were reported for each metal. SGM states that in 1892 two smelters were built and operated (Magdalena Teitipac and O'Kelly) near the village of Tlacolula for processing ores from the Alta Gracia, La Soledad, San Ignacio y Anexas, La Leona, La Victoria, and San Rafael silver mines. Subsequently, in 1911, Mr. Sken Sanders investigated the Totolapam mining region with a particular interest in the Margaritas mine. Most of these historical mines are situated within DDGM's mining concessions.

      The Arista and Alta Gracia Projects are in the smaller mining sub-districts of San Jose de Gracia and Alta Gracia, respectively. Only small-scale artisanal mining has been historically conducted in these sub-districts. No reliable production records exist for the historic production performed in the Arista and Alta Gracia Project areas.

      The Arista Project mining district had been inactive since the 1950s, and the Alta Gracia Project mining district since the 1980s, until Apex Silver Corporation ("Apex") began exploration work in the 1990s. Subsequently, GRC initiated geologic reconnaissance through its Mexican subsidiaries in search of precious metal deposits.

      As of December 31, 2025, DDGM holds an interest in 29 mining concessions in Oaxaca State totaling 55,119 hectares. Concession expiration dates range from August 30, 2049 to February 22, 2073.

   2. Exploration History

      GRC has carried out a continuous drilling program since 2003, when the company took control of the Arista Project mining concessions, now part of GRC's Don David Gold Mine. GRC continues an aggressive exploration program that includes underground mine development, such as access ramps, drifts, and crosscuts to support drilling and access in the Arista, Switchback, Three Sisters and Alta Gracia vein systems.

      In the 1940s, exploration audits were mined into the Manto vein; however, the results of this activity were not reported. In the 1980s, mining took place in the Alta Gracia Project area. Again, no information on exploration activity is available.

      In 1998 - 1999, prior to GRC's involvement, several DDGM concessions were leased to Apex. Apex conducted an exploration program involving geologic mapping, surface sampling, and an 11-hole (1,242 m) RC drilling program targeting the Manto vein, a shallow-dipping manto-style deposit.

      GRC exploration and drilling activities are discussed in the relevant sections of this Technical Report.

   3. Prior Mineral Resources and Mineral Reserves

      All previously reported Mineral Resource and Mineral Reserve estimates are regarded as prior estimates and are superseded by the current Mineral Resources and Mineral Reserves presented in this report.

   4. Production History

   The Arista and Alta Gracia Project areas are located within the smaller mining sub-districts of San Jose de Gracia and Alta Gracia, respectively. Historically, only small-scale artisanal mining has been conducted in these sub-districts, and no reliable production records exist for historic production in the Arista and Alta Gracia Project areas.

   Modern mining at the Arista Project commenced from an open pit in 2010 and continued through 2011. Underground mining commenced in the Arista vein system in 2011, followed by the Switchback deposit vein system in 2017 and the Three Sisters vein system in 2025. Underground production from these vein systems continued in 2025. In addition, DDGM mined and/or processed ore from the Alta Gracia Project (Mirador and Independencia vein systems) from 2017 through 2020.

   Since the commencement of production from the Don David Gold Mine in 2010, DDGM has produced 394,219 ounces of gold and 28,409,892 ounces of silver from the 6,620,105 tonnes shipped to the DDGM Processing Facility (Table 0-9). In addition, 17,511 tonnes of copper, 73,457 tonnes of lead, and 201,692 tonnes of zinc have been produced from the plant.

   Table 0-9: Don David Mine Production 2010 through 2025.

   YEAR	MILLED TONNES	GOLD OZ	SILVER OZ	COPPER TONNES	LEAD TONNES	ZINC TONNES
   2010	166,237	10,493	111,316
   2011	214,215	21,586	2,180,309	620	1,840	3,730
   2012	282,120	34,417	2,996,743	986	3,374	9,115
   2013	316,270	33,942	3,032,841	926	2,742	7,452
   2014	375,623	35,552	3,297,204	1,254	4,555	13,195
   2015	413,626	29,644	2,506,337	1,310	4,174	13,900
   2016	450,221	27,628	1,857,658	1,035	4,049	14,302
   2017	449,177	28,117	1,773,263	1,141	5,365	16,301
   2018	611,670	26,838	1,672,034	1,652	7,280	19,808
   2019	693,173	29,435	1,722,852	1,859	9,202	23,683
   2020	565,346	20,473	1,189,366	1,593	7,725	19,696
   2021	501,978	26,438	1,200,291	1,506	7,544	17,696
   2022	493,241	34,122	1,213,404	1,436	6,665	17,943
   2023	459,171	20,328	1,142,138	1,287	5,068	13,513
   2024	356,633	9,906	919,836	642	2,682	7,745
   2025	271,404	5,300	1,594,300	264	1,192	3,613
   Totals	6,620,105	394,219	28,409,892	17,511	73,457	201,692

6. GEOLOGICAL SETTING AND MINERALIZATION AND DEPOSIT

Late structural events are suspected of playing a significant role in the current configuration of vein positions (Figure 0-8), with the most prominent trend-oriented 340-350° (sinistral strike-slip, ± oblique thrust). Many veins, including Baja, exhibit internal deformation (multiphase concurrent with mineralization and post mineralization), and several veins and splays, including Arista and Vein 3, are suspected of having been juxtaposed side-by-side by the post mineralizing events, such that an artificial thickening of veins results from transposition or "stacking." To support this interpretation, evidence has been documented on measurable fault surfaces exposed in the upper levels of current mine workings on the Arista fault vein, Vein 3, and Baja vein. Likewise, bonanza grades have been attributed to these intersecting structural sites.

A consultant geologist performed additional structural work in 2018 (Hohbach, 2018) on the Switchback vein system, where similar transposition features are also seen in the principal veins. Hohbach identified four main mineralized structural orientations, which are, from oldest to youngest:

1. F290-305°: parallel to regional features such as the Rio Grande trend, with oblique-slip and right lateral motions interpreted; often associated with higher-grade mineralization.

2. F310-320°: normal faults with dip to oblique-slip movements, with generally confined mineralization.

3. F340°: parallel deep-seated fractures. With generally confined mineralization and an association with late felsic dykes.

4. F090-270°: swarms of E-W fractures. They are generally very steep and can host narrow high-grade veins; Hohbach postulates that they are conjugate to the F290-305° set.

Hohbach also identified several preferred post-mineralization orientations, namely: FN0°, F60°, F90° (which can be confused with the mineralized set and can have notable offsets), and F325-330°, which can manifest as significant fault zones with significant gouge thicknesses. All can have fault gouge and show minimal mineral alteration.

Most of the mineralized orientations correlate to directions identified by SRK for the Arista vein system.