Gold Resource : Q4 Financial Report (goro gold resource corporation annual report pursuant to section 13 or 15 d 10 k 2026 03 18)

(Mark One)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2025

• TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
  

  For the transition period from to
  

  Commission File Number: 001-34857
  

  Gold Resource Corporation

  (Exact name of registrant as specified in its charter)

  Colorado 84-1473173
  

  (State or other jurisdiction of incorporation or organization)

  (I.R.S. Employer Identification No.)

  7900 E. Union Ave, Suite 320, Denver, Colorado 80237
  

  (Address of Principal Executive Offices) (Zip Code)

  (303) 320-7708
  

  (Registrant’s telephone number including area code)

  Securities registered pursuant to Section 12(b) of the Act:

  Title of each class	Trading Symbol	Name of each exchange on which registered
  Common Stock, $0.001 par value	GORO	NYSE American

  
  Securities registered pursuant to Section 12(g) of the Act: None
  

  Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☐ No

  Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐ No

  Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such

  shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes

  No ☐

  Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes

  No ☐

  Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See definition of “large accelerated filer,” “accelerated filer”, “smaller reporting company”, and “emerging growth company” in Rule 12b-2 of the Exchange Act.

  Large accelerated filer
  Non-accelerated filer	Smaller reporting company
  	Emerging growth company

  If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act ☐

  Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C.7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☐

  If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

  Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

  Indicate by check mark whether registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No

  The aggregate market value of the common stock of Gold Resource Corporation held by non-affiliates as of June 30, 2025, the last business day of the registrant’s most recently completed second fiscal quarter, was $83,177,835 based on the closing price of the common stock of $0.61 as reported on the NYSE American.

  As of March 16, 2026, there were 161,858,849 shares of the registrant’s common stock outstanding.

  DOCUMENTS INCORPORATED BY REFERENCE:

  Portions of the Definitive Proxy Statement to be filed pursuant to Regulation 14A for the registrant’s 2026 annual meeting of shareholders will be filed no later than 120 days after the close of Registrant’s fiscal year ended December 31, 2025, and are incorporated by reference into Part III of this Form 10-K.

  ‌TABLE OF CONTENTS

  Page
  

  2025 Summary 2

  PART I

  ITEM 1: Business 6

  ITEM 1A: Risk Factors 12

  ITEM 1B: Unresolved Staff Comments 27

  ITEM 1C: Cybersecurity 27

  ITEM 2: Properties 29

  ITEM 3: Legal Proceedings 45

  ITEM 4: Mine Safety Disclosures 45

  PART II

  ITEM 5:	Market For Registrant’s Common Equity , Related Stockholder Matters, and Issuer Purchases of Equity Securities	46
  ITEM 6:	Reserved	46
  ITEM 7:	Management’s Discussion and Analy sis of Financial Condition and Results of Operations	47
  ITEM 7A:	Quantitative and Qualitative Disclosures About Market Risk	65
  ITEM 8:	Financial Statements	67
  ITEM 9:	Changes in and Disagreements with Accountants on Accounting and Financial Disclosure	105
  ITEM 9A:	Controls and Procedures	105
  ITEM 9B:	Other Information	106
  ITEM 9C:	Disclosures Regarding Foreign Jurisdictions that Prevent Inspections	106

  PART III

  ITEM 10:	Directors, Executive Officers, and Corporate Governance	107
  ITEM 11:	Executive Compensation	107
  ITEM 12:	Security Ownership of Certain Beneficial Owners and Management and Related
  	Stockholder Matters	107
  ITEM 13:	Certain Relationships and Related Transactions, and Director Independence	107
  ITEM 14:	Principal Accounting Fees and Services	107

  PART IV

  ITEM 15:	Exhibits and Financial Statement Schedules	108
  ITEM 16:	Form 10-K Summary	110
  	Signatures	111

  Gold Resource Corporation

  1

  ‌2025 SUMMARY

  Milestones for the full-year ended December 31, 2025 are included below and discussed further under Item 7-Management’s Discussion and Analysis of Financial Condition and Results of Operations:

  Don David Gold Mine:

  • Production substantially improved, as the Company began receiving newly acquired equipment at the end of the third quarter. The additional equipment, combined with the strategic use of third-party contractors, enabled an increase in available production headings and a subsequent improvement in production.

  • DDGM produced and sold a total of 23,125 gold equivalent ounces, comprising of 4,944 gold ounces and 1,461,898 silver ounces, sold at an average price per ounce of $3,657 and $45.48, respectively. DDGM total cash costs after co-product credits per gold equivalent (“AuEq”)1 ounce sold and DDGM all-in sustaining cost per AuEq ounce sold for the year were $2,205 and $2,807, respectively. See Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations-Non-GAAP Measures below for a reconciliation of non-GAAP measures to applicable GAAP measures.

  • DDGM received the Mexican Empresa Socialmente Responsable (“ESR”) award in 2025 for the eleventh consecutive year.

  • During 2025, the Company’s exploration program focused on underground grade-control and infill drilling in support of near-term production, primarily in the Three Sisters and Arista vein systems. At Three Sisters, drilling targeted the Sandy and Sadie vein sets to refine and validate the geologic model for production planning. Additional definition drilling was completed on multiple veins within the Arista system, including Splay 31, Candelaria, Marena, Santa Helena, Viridiana, and Marena North, as well as the Soledad South vein in the Switchback vein system. Exploration-related underground development advanced throughout the year, positioning the Company to continue expansion drilling in early 2026. In addition, limited surface infill drilling also commenced at the Alta Gracia mine in the fourth quarter, focusing on the Mirador vein system.

    Corporate and Financial:

  • The Company closed the year with a $25.0 million cash and cash equivalents balance at December 31, 2025. The increase of $23.4 million from December 31, 2024 is the result of the Company’s focus on improving its cash position, mostly through the issuance of debt and equity in 2025, as well as improved production and higher metal prices.

    • The Company raised $2.5 million through a registered direct offering in January 2025. In September 2025, the Company closed on a second registered direct offering of $11.4 million for the sale of 25,315,954 shares of the Company’s common stock at a price of $0.45 per share. The Company issued 14,204,846 of these shares, for the fair value of approximately $6.4 million, to fully pay off the term loan received in June 2025, as a non-cash equity settlement.

    • The Company raised $8.6 million through its At-The-Market Offering Program (the “ATM Program”), after deducting the agent’s commissions and other expenses.

    • In February 2025, the Company sold its interest in Green Light Metals for $0.9 million in proceeds.

    • On May 7, 2025, the Company received a tax refund of 79.6 million pesos (approximately $4.0 million) related to DDGM taxes paid in 2023.

  • Working capital at December 31, 2025, was $32.0 million, a 1,424% increase from the December 31, 2024 working capital of $2.1 million. The increase is primarily driven by the increase in cash and cash equivalents.

1 Gold equivalent is determined by taking gold ounces produced and sold, plus silver ounces produced and sold, converted to gold equivalent ounces using the gold to silver average realized price ratio for the period.

Gold Resource Corporation

2

Liquidity Update

The Company has significantly improved its financial position in 2025. Although tonnes produced from the mining operations at DDGM in full year 2025 remained lower than in the previous year, production substantially improved in the fourth quarter of 2025. Due to the age and condition of some of the critical mining equipment used at the mine, the Company started to encounter significant issues with equipment availability in 2024. To overcome this issue, the Company engaged a third-party contract miner during the third quarter of 2025 and also started to upgrade its mining fleet. As a result, by the end of the third quarter, the Company was able to increase production from a number of production headings.

The Company believes that the mine has the potential to generate positive cash flow based on the information to date from the new Three Sisters area, as well as other zones that have been discovered near existing headings. The Company started developing access to and drill-defining these new areas. With the improvements mentioned above, the Company had an improved operating income in the fourth quarter of 2025 and expects 2026 to result in positive operating income.

In 2025, the Company focused on improving its cash position, mostly through the issuance of debt and equity. The Company raised $2.5 million through a registered direct offering in January 2025. In February 2025, the Company sold its interest in Green Light Metals for $0.9 million in proceeds. On May 7, 2025, the Company received a tax refund of 79.6 million pesos (approximately $4.0 million) related to DDGM taxes paid in 2023. In September 2025, the Company closed on a second registered direct offering of $11.4 million for the sale of 25,315,954 shares of the Company’s common stock at a price of $0.45 per share. The Company issued 14,204,846 of these shares, for the fair value of approximately $6.4 million, to fully pay off the term loan received in June 2025 as a non-cash equity settlement. During 2025, the Company raised approximately $8.6 million through its ATM Program, after deducting the agent’s commissions and other expenses.

Gold Resource Corporation

3

FORWARD-LOOKING STATEMENTS

This report contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. The Company uses the words “anticipate,” “continue,” “likely,” “estimate,” “expect,” “may,” “could,” “will,” “project,” “should,” “believe,” and similar expressions (including negative and grammatical variations) to identify forward looking statements. Such forward-looking statements include, without limitation, statements regarding:

• The Company’s ability to satisfy its financial and contractual obligations and other potential cash requirements over the next twelve months;

• The Company’s anticipated near-term capital requirements and potential sources of capital;

• Expectations regarding 2026 general and administrative costs;

• The Company’s expectations regarding whether dividends will be paid in the future;

• Compliance with existing legal and regulatory requirements, including future asset reclamation costs;

• The Company’s strategy for significant future investment in Oaxaca, Mexico, and in Michigan, USA, for development and exploration activities;

• Expectations regarding capital investment, exploration spending, and general and administrative costs, including the Company’s near-term estimates for the cost of additional mining equipment, mill upgrades, and working capital;

• The Company’s expectations regarding future grades and recoveries from mining at DDGM; and its expectations regarding its ability to generate positive cash flow from future production at DDGM;

• Future exploration plans at DDGM, including vein systems targeted for future exploration activity;

• Estimates of Mineral Resources and Mineral Reserves;

• The sufficiency of the Company’s water rights;

• The Company’s expectation for the outcome of the 2015 DDGM tax audit;

• Expectations regarding 2026 DDGM and Back Forty capital investments;

• The expected timetable for and completion of the potential Transaction (as defined in Item 1. Business-Recent Developments); and

• The expected timing and success of the Back Forty Project with respect to additional feasibility study work, engineering, permitting, and project financing.

  Forward-looking statements are neither historical facts nor assurances of future performance. Rather, they are based only on the Company’s current beliefs, expectations, and assumptions regarding the future of its business, future plans and strategies, projections, anticipated events and trends, the economy, and other future conditions. Because forward-looking statements relate to the future, they are subject to inherent uncertainties, risks, and changes in circumstances that are difficult to predict, and many of which are outside of the Company’s control. The Company’s actual results and financial condition may differ materially from those indicated in the forward-looking statements. Therefore, you should not rely on any of these forward-looking statements. Important factors that could cause the Company’s actual results and financial condition to differ materially from those indicated in the forward-looking statements include, among others, the following:

• Risks associated with the Company’s ability to complete the proposed Transaction on the terms anticipated or at all;

• Whether the Company is able to raise the necessary capital required to continue its business on terms acceptable to it or at all;

• The possibility of unforeseen production or processing challenges at DDGM, such as mechanical breakdowns, staffing shortages, weather events, unexpected decreases in grade, lower than anticipated production at existing mining faces, or inability or delays in the access and development of new mining faces;

• Commodity price fluctuations;

• Mine protests and work stoppages;

• Rock formations, faults and fractures, water flow and possible CO2 gas exhalation, or other unanticipated geological challenges;

  Gold Resource Corporation

  4

• Unexpected changes in business and economic conditions, including supply chain challenges, the rate of inflation, fuel price, and their impact on operating and capital costs;

• Changes in interest rates and currency exchange rates;

• Adverse technological changes and cybersecurity threats;

• Unanticipated increases in the Company’s operating costs and other costs of doing business;

• Access to land and availability of materials, equipment, supplies, labor and supervision, power, and water;

• Results of current and future feasibility studies;

• Interpretation of drill hole results and the geology, grade, and continuity of mineralization;

• Litigation by private parties or regulatory action by governmental entities;

• Acts of God, such as excessively wet weather, floods, earthquakes, and any other natural disasters;

• Changes in investor perception of the Company and/or the mining industry;

• The inherent uncertainty of Mineral Resources and Mineral Reserves estimates;

• The Company’s internal controls over financial reporting; and

• Such other factors are discussed below under Item 1A. Risk Factors.

Many of these factors are beyond the Company’s ability to control or predict. Although the Company believes that the expectations reflected in its forward-looking statements are based on reasonable assumptions, such expectations may prove to be materially incorrect due to known and unknown risks and uncertainties. You should not unduly rely on any of the Company’s forward-looking statements. These statements speak only as of the date of this annual report on Form 10-K. Except as required by law, the Company is not obligated to publicly release any revisions to these forward-looking statements to reflect future events or developments. All subsequent written and oral forward-looking statements attributable to the Company and persons acting on its behalf are qualified in their entirety by the cautionary statements contained in this section and elsewhere in this annual report on Form 10-K.

Gold Resource Corporation

5

‌PART I

‌ITEM 1. BUSINESS

History and Organization

In this report, “Company” and “GRC” refer to Gold Resource Corporation together with its subsidiaries, unless the context otherwise requires. See Item 2. Properties-Glossary for additional definitions.

The Company was organized under the laws of Colorado, USA on August 24, 1998. Since 2010, the Company has produced gold and silver doré and copper, lead, and zinc concentrates in Oaxaca, Mexico at its subsidiary, Don David Gold Mexico S.A. de C.V. (“Don David Gold Mine” or “DDGM”). The Don David Gold Mine holds six properties located in what is known as the San Jose structural corridor. The Company’s properties span 55 continuous kilometers of this structural corridor, which include three historic mining districts in Oaxaca.

On December 10, 2021, the Company successfully completed the acquisition of all the issued and outstanding common shares of Aquila Resources Inc. (“Aquila”). Aquila’s principal asset is its 100% interest in the Back Forty Project located in Menominee County, Michigan, USA. The Back Forty Project has a polymetallic (gold, silver, copper, lead, and zinc) Volcanogenic Massive Sulfide deposit. The Back Forty Project controls surface and mineral rights through ownership and leases with the State of Michigan. Optimization work related to metallurgy and the economic model was completed during the third quarter of 2023, and the Company released the Back Forty Project Technical Report Summary, effective as of September 30, 2023, on October 26, 2023 (the “Back Forty Project Technical Report Summary”). Results of the work indicate a more robust economic project with no planned impacts to wetlands that is more protective of the environment, which should facilitate a successful mine permitting process. The Company is currently in discussions to complete a feasibility study and to move forward with the permitting process for the Back Forty Project.

Gold Resource Corporation

6

Mexico Production Stage Properties:

The primary production stage properties at DDGM commenced operations in 2010. Current operations include the Arista underground mine and the DDGM processing facility, which produces metal concentrates from ore mined at the Arista Mine. The Arista Mine was expanded in 2016 with the development of the Switchback vein system and again in 2025 with the development and initial production of the Three Sisters vein system. The Arista Mine portal is located approximately two kilometers from the processing facility. Additionally, underground mining was conducted from 2017 to 2019 at the Alta Gracia Mine, where limited surface drilling recommenced in the fourth quarter of 2025. Alta Gracia is approximately 32 kilometers from the DDGM processing facilities.

The Arista and Alta Gracia Mines include a total of approximately 30,000 hectares of mining concessions, access roads from a major highway, haul roads, a processing facility and adjoining buildings, an assay lab, a now depleted open pit, underground mines, tailings facilities, and other infrastructure. Please see Item 2. Properties for additional information.

Mexico Exploration Prospects:

The Company’s current land package sits within the highly prospective 55-kilometer-long San Jose structural corridor, in Oaxaca, Mexico. Multiple volcanic domes of various scales, and likely non-vented intrusive domes, dominate the district geology. These volcanogenic features are imposed on a pre-volcanic basement of sedimentary rocks. Gold and silver, as well as base metal mineralization in this district is related to the manifestations of this classic volcanogenic system and is considered epithermal in character. The Company intends to advance organic growth and to unlock the value of the mine, existing infrastructure, and its large property position by continuing to invest in exploration and development. Please see Item 2. Properties for additional information.

Processing Plant at Night

Gold Resource Corporation

7

Back Forty Project:

There is a long history of exploration at the Back Forty Project. After the acquisition of Aquila and the Back Forty Project by the Company in 2021, optimization work was initiated to address the mine’s footprint, potential for an underground mine, wetland mitigation, and other key construction and design decisions. This optimization work related to a change in mine design, tailings relocation, and metallurgy. The economic model was completed, and the Company released the Back Forty Project Technical Report Summary on October 26, 2023. Results of the work indicate a more robust economic project with no planned impacts to wetlands that are more protective of the environment, which should facilitate a successful mine permitting process expected to start in 2026. With much higher metal prices since the Back Forty Project Technical Report Summary was completed, the Board actively evaluates the options that could lead to the successful development of the project. Please see Item 2. Properties for additional information.

Before the Aquila acquisition, Aquila’s common shares were traded on the Toronto Stock Exchange (“TSX”) under the ticker symbol AQA. Effective December 10, 2021, Aquila ceased to be a reporting issuer in British Columbia, Alberta, Saskatchewan, Ontario, and Nova Scotia. At the same time, GRC became a reporting issuer in British Columbia, Alberta, Saskatchewan, Ontario, and Nova Scotia by virtue of the completion of the acquisition. As a Canadian reporting issuer, GRC is now required to file reports on the System for Electronic Document Analysis and Retrieval (“SEDAR”) in Canada. All financial statements filed on SEDAR conform to United States generally accepted accounting principles (“U.S. GAAP”).

Administrative Offices:

The Company’s principal executive offices are located at 7900 E. Union Ave, Suite 320, Denver, Colorado 80237, and its telephone number is (303) 320-7708. The Company maintains a website at www.goldresourcecorp.com. Information on its website is not incorporated into this annual report on Form 10-K and is not a part of this report. The U.S. Securities and Exchange Commission (“SEC”) maintains an internet site (www.sec.gov) on which the reports that the Company files with the SEC are available to review. The SEC filings can also be accessed through the Company’s website.

Gold Resource Corporation

8

2025 Development Highlights

For the year ended December 31, 2025, the Company reported a net loss of $6.5 million. Despite the net loss reported for the year, the Company’s operating mine is showing improvements and a turnaround in performance that is mainly attributable to higher metal prices and improved production as a result of acquired new equipment, as well as the use of a third-party mining contractor, allowing the development of higher-grade areas of the deposit. Financial results for 2025 include revenue of $99.8 million and mine gross profit of $26.8 million. The Company’s production results for the year totaled 5,300 gold ounces, 1,594,300 silver ounces, 264 copper tonnes, 1,192 lead tonnes, and 3,613 zinc tonnes.

For the eleventh consecutive year, DDGM received the prestigious ESR award from the Mexican Center for Philanthropy (“CEMEFI”). Awards are given to organizations that demonstrate a commitment to supporting social and environmental protection programs within their local communities.

The Company’s exploration activities focused on underground drilling within the Arista, Switchback, and Three Sisters vein systems of the Arista mine, along with limited surface drilling at the Alta Gracia deposit beginning in the fourth quarter. During the year, the Company completed a total of 111 diamond drill holes totaling 14,539 meters, consisting of 33 infill holes totaling 5,982 meters, and 78 grade-control holes totaling 8,557 meters. Of the infill drilling, six holes totaling 1,121 meters were completed from surface at Alta Gracia. The Company also completed more than 485 meters of underground drift development in 2025 to support ongoing infill and grade-control drilling and to facilitate planned expansion drilling in 2026.

Exploration efforts were primarily dedicated to underground drilling on multiple high-grade, polymetallic epithermal veins within the Three Sisters vein system, particularly the Sandy and Sadie vein sets, and within the Arista vein system, including the down-dip and northern extension of the Viridiana and Marena veins, as well as the northern extensions of the Splay 31 and Marena North veins. The 2025 drilling program was designed to support Mineral Reserve

definition and to define additional Mineral Resources. The Three Sisters vein system lies between and north of the Arista and Switchback systems and is located near existing mine infrastructure. Following focused infill and grade-control drilling during the year, a total of 24 distinct veins and vein segments, including the Gloria vein, have now been delineated. Both the Three Sisters and northern Arista vein systems remain the primary targets for infill and expansion drilling in 2026. Updated 2025 resource models for all three vein systems incorporated tighter geologic and economic constraints, resulting in more selective and geologically constrained estimates. In particular, drilling within the Three Sisters and Arista systems resulted in an upgrade of a portion of the previously reported Inferred Mineral Resources to Measured and Indicated categories; increasing confidence in those areas. All vein systems remain open for further expansion drilling both up- and down-dip, as well as along strike to the northwest.

Surface exploration during 2025 included the initiation of a limited surface infill drilling program at Alta Gracia in mid-November. By year-end, six infill holes totaling 1,121 meters had been completed, targeting the upgrade of previously defined Inferred Mineral Resources in the upper southwestern portion of the Mirador vein. The Company also continued evaluating and prioritizing advanced-stage exploration targets within the approximately 551 square kilometer land package controlled by DDGM surrounding the Arista Mine. These activities included the reprocessing and integration of historical geologic information, including mapping, sampling, geophysical surveys, and drill data, from several projects, including Rey, Alta Gracia, Margaritas, El Fuego, Chamizo, and Jabali. Prospective areas proximal to the Arista Mine were also re-evaluated for near-term exploration potential with the objective of defining additional near-mine drill targets. These ongoing efforts support the Company’s long-term exploration strategy and continued operational presence in Oaxaca, Mexico.

Gold Resource Corporation

9

In connection with the Back Forty Project, the Company continues to monitor the U.S. Army Corps of Engineers’ (“USACE”) review of a petition by the Menominee Indian Tribe of Wisconsin (“MITW”) requesting that the Menominee River be designated as navigable under Section 10 of the Rivers and Harbor Act. The USACE has previously concluded, based on prior studies, that the relevant reach of the Menominee River in the project area does not meet the federal definition of navigability. The MITW has requested that the Environmental Protection Agency and the USACE evaluate whether federal agencies, rather than the State of Michigan, should exercise regulatory authority over certain activities potentially requiring federal permits. Based on the current project design and permitting framework, the Company does not presently anticipate the need for additional federal permits related to navigability of the river corridor, however any change in jurisdictional determinations could affect future permitting requirements. In response to the MITW petition, the USACE is updating its navigability study for the Menominee River, which was expected to be completed in 2023, but it’s still under final administrative review.

Recent Developments

On January 26, 2026, the Company announced that it has entered into a definitive arrangement agreement and plan of merger (the “Arrangement Agreement”) with Goldgroup Mining Inc. (“Goldgroup”), whereby Goldgroup has agreed to acquire all of the issued and outstanding shares of the Company’s common stock (the “Transaction”).

Pursuant to the Arrangement Agreement, the Company’s stockholders will receive 1.4476 common shares of Goldgroup for each share of the Company’s common stock (adjusted to 0.3619 common shares of Goldgroup for each share of the Company’s common stock as a result of a four-for-one share consolidation to be completed by Goldgroup prior to closing). The proposed Transaction will occur by way of a reverse triangular merger in which the Company will merge with a wholly owned subsidiary of Goldgroup under Colorado law and a plan of arrangement under the Business Corporations Act (British Columbia), with the Company surviving as a wholly owned subsidiary of Goldgroup. Upon completion of the Transaction, the Company’s stockholders are expected to own approximately 40% of the combined company on a fully diluted in-the-money basis.

The Transaction was unanimously approved by the boards of directors of the Company and Goldgroup. The Transaction is expected to close in the second quarter of 2026, subject to customary closing conditions (including approval by the stockholders of each of the Company and Goldgroup and approval by the Mexican National Antitrust Commission). Upon closing, the board of directors of Goldgroup will be comprised of three directors selected by Goldgroup and two directors selected by the Company. The parties anticipate that the executive management team of the Company will become the officers of the combined company.

Dividends

In February 2023, to conserve cash for development and equipment expenses, the Company announced the suspension of its quarterly dividend until such time that it may become practicable to reinstate such dividend. Please see Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchase of Equity Securities for additional information regarding the Company’s dividend policy.

Insurance

The Company’s business is capital intensive and requires ongoing investment for the replacement, modernization, or expansion of equipment and facilities. For more information, please see Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations-Liquidity and Capital Resources below. The Company maintains insurance policies against property loss and business interruption and insure against most risks that are typical in the operation of its business in amounts that the Company believes to be reasonable. Such insurance, however, contains exclusions and limitations on coverage, particularly with respect to property loss, environmental liability, and political risk. There can be no assurance that claims would be paid under such insurance policies in connection with a particular event. Please see Item 1A. Risk Factors below for additional information.

Gold Resource Corporation

10

Competitive Business Conditions

The acquisition of gold and silver properties is subject to intense competition. Identifying and evaluating potential mining prospects is a costly and time-consuming endeavor. In 2021, the Company successfully acquired the Back Forty Project as discussed above. The Company expects to continue significant investment in exploration and growth activities in the future; however, competition for acquiring mineral prospects will continue to be intense.

Government Regulations and Permits

In connection with mining, milling, and exploration activities in Mexico, the Company is subject to Mexican federal, state, and local laws and regulations governing the protection of the environment, including laws and regulations relating to the protection of air and water quality, hazardous waste management, mine reclamation, as well as the protection of endangered or threatened species. The government department responsible for environmental protection in Mexico is Secretaria de Medio Ambiente y Recursos Naturales (“SEMARNAT”). SEMARNAT has broad authority over environmental regulations and standards. Potential areas of environmental consideration for mining companies include, but are not limited to, acid rock drainage, cyanide containment and handling, contamination of water sources, dust, and noise.

For operations at the Don David Gold Mine, the Company has secured and continues to maintain various regulatory permits from federal, state, and local agencies. These governmental and regulatory permits generally govern the processes being used to operate, the stipulations concerning air quality, water issues, hazardous materials and waste management, and the plans and obligations for reclamation of the properties at the conclusion of operations. These laws and regulations are continually changing and are generally becoming more restrictive.

The Company’s production stage mines in Mexico have reclamation plans in place that it believes meet all applicable legal and regulatory requirements. As of December 31, 2025, $10.2 million has been accrued on the Company’s Consolidated Balance Sheets for reclamation costs relating to its production and exploration stage properties in Mexico. In addition, the Company accrued $0.1 million for drill-hole plugging on the Company’s Consolidated Balance Sheets for reclamation costs relating to its exploration stage property in Michigan.

The State of Michigan has been delegated authority under federal environmental law to issue all necessary environmental permits required for the Back Forty Project. The State of Michigan’s “Natural Resource Environmental Protection Act” provides rules and regulations for the State Department of Environment, Great Lakes and Energy (EGLE) to issue permits for mining, treated wastewater discharge, air emissions, and related environmental permits necessary for the Back Forty Project.

Customers

During the year ended December 31, 2025, two customers accounted for 99% of the Company’s revenue from DDGM. In the event that the Company’s relationship with any of its customers is interrupted for any reason, the Company believes that it would be able to locate another entity to purchase its products in a timely manner on substantially similar terms. However, any interruption could temporarily disrupt the sale of the Company’s principal products and materially adversely affect its operating results. The Company periodically reviews its options for alternative sales outlets to mitigate the concentration of risk in case of any unforeseen disruptions.

Human Capital Resources

The Company values excellence and recognizes that embracing the diverse backgrounds, skills, and perspectives of the local workforce will lead to a competitive advantage. The Company is committed to leading by example and maintaining a fair and inclusive work environment built on mutual respect and integrity. Diversity means understanding, accepting, respecting, and valuing differences among people regardless of age, gender, race, ethnicity, culture, religion or spiritual practices, disabilities, sexual orientation, gender identity, family status, or veteran status.

Gold Resource Corporation

11

The Company believes it has good morale and a dedicated workforce. The Company’s human capital resources objectives include, as applicable, identifying, recruiting, retaining, incentivizing, and integrating its existing employees and new hires. The principal purposes of the Company’s equity incentive plans are to attract, retain, and motivate selected employees and directors by granting stock-based compensation awards that align employee compensation with shareholder returns.

DDGM Employee Housing

As of December 31, 2025, the Company had 485 employees at DDGM. There were 12 full-time corporate employees, two of whom serve as executive officers, and three full-time employees in Michigan who are fully dedicated to progressing the Back Forty Project.

‌ITEM 1A. RISK FACTORS

The Company’s business, and the mining industry in general, is influenced by significant risks and uncertainties. These risks include those described below and may include additional risks and uncertainties not presently known or currently deemed immaterial. The Company’s business, financial condition, and results of operations could be materially adversely affected by any of these risks, and the trading price of the Company’s common stock could decline by virtue of these risks. These risks should be read in conjunction with the other information in this annual report on Form 10-K.

Financial Risks

The Company’s results of operations, cash flows, and the value of its properties are highly dependent on the market prices of gold, silver, and certain base metals, and these prices can be volatile.

The profitability of the Company’s mining operations and the value of its mining properties are directly related to the market price of gold, silver, copper, lead, and zinc. The price of gold and silver may also significantly influence the market price of the Company’s common stock. The market prices of these metals historically have fluctuated significantly and are affected by numerous factors beyond the Company’s control, including (i) global or regional consumption patterns;

(ii) supply of and demand for gold, silver, and base metals on a worldwide basis; (iii) speculative and hedging activities;

Gold Resource Corporation

12

1. expectations for inflation; (v) political and economic conditions; (vi) supply of, and demand for, consumables required for extraction and processing of metals, and (vii) general economic conditions worldwide. Over the last five years (as reported on the London Bullion Market Association using the London PM Fix for gold and silver), gold prices have fluctuated from a low of $1,629 per ounce to a high of $4,449 per ounce, and silver prices have fluctuated from a low of

   $17.77 per ounce to a high of $74.84 per ounce. On December 31, 2025, the London PM Fix gold price was $4,368 per ounce, and the London PM silver price was $71.99 per ounce.

   Currently, the Company does not use hedging transactions with respect to any of its metal production. Accordingly, the Company is fully exposed to price fluctuations in precious metals. In the event metal prices decline or remain low for prolonged periods of time, the Company might be unable to develop its exploration properties, which may materially adversely affect its results of operations, financial performance, and cash flows. An asset impairment charge may result from the occurrence of unexpected adverse events that impact the Company’s estimates of expected cash flows generated from its mining operations or the market value of its non-producing properties, including a material diminution in the price of metals.

   The Company may not achieve profitability.
   

   The Company’s only production-stage property that produces revenue is DDGM in Mexico, and it may not generate sufficient cash flow to cover the Company’s operating, development, exploration, general and administrative, and other costs due to certain risk factors. Unexpected interruptions in the mining business may cause the Company to incur losses, or the revenue that is generated from extraction may not be sufficient to fund continuing operations, including exploration and mine development costs. The Company’s failure to generate future profits may materially adversely affect the price of its common stock, and stockholders may lose all or part of their investment. Metal prices and foreign currency rates have a significant impact on the Company’s profit margin, and there is no assurance that the Company will be profitable in the future. Please see Item 1A. Risk Factors-Financial Risks-The Company’s results of operations, cash flows, and the value of its properties are highly dependent on the market prices of gold, silver, and certain base metals and these prices can be volatile.

   The Company requires access to additional capital in order to finance its business plans, and there is no guarantee the Company will have access to that capital on favorable terms, or at all.
   

   The Company requires significant funds to develop, access, and determine if Mineral Reserves exist at any of its non-producing properties, continue exploration, and if warranted, develop existing properties and identify and acquire additional properties to diversify its property portfolio.

   The Company’s ability to obtain necessary funding for these purposes, in turn, depends upon several factors, including historical and prospective results of operations, the status of the national and worldwide economy, the price of gold, silver, and other metals, the condition of the debt and equity markets, the costs associated with extracting and acquiring minerals, and the market value for its common stock. The Company may not be successful in generating or obtaining the required financing, or if it can obtain such financing, such financing may not be on terms that are favorable to the Company and its shareholders. The Company also may be unable to obtain funding by monetizing additional non-core exploration or other assets at an acceptable price.

   The Company cannot provide assurance it will be able to obtain financing to fund its general and administrative costs and other working capital needs to fund continuing business activities in the future on favorable terms, or at all. Failure to obtain funds could result in delay or indefinite postponement of further mining operations, exploration, and construction, as well as the possible partial or total loss of the Company’s interest in its properties.

   Gold Resource Corporation

   13

   The Company’s ability to recognize the benefits of deferred tax assets is dependent on future cash flows and taxable income.
   

   The Company recognizes deferred tax assets when the tax benefit is more likely than not to be realized; otherwise, a valuation allowance is applied against deferred tax assets. Assessing the recoverability of deferred tax assets requires management to make significant estimates related to expectations of future taxable income. Estimates of future taxable income are based on forecasted cash flows from operations and the application of existing tax laws in each jurisdiction. To the extent that future cash flows and taxable income differ significantly from estimates, the Company’s ability to realize the deferred tax assets could be impacted, if applicable. Additionally, future changes in tax laws could limit the Company’s ability to realize the future tax benefits represented by its deferred tax assets.

   The Company’s accounting and other estimates may be imprecise.

   Preparing financial statements requires management to make estimates and assumptions that affect the reported amounts and related disclosure of assets, liabilities, revenue, and expenses at the date of the consolidated financial statements and reporting periods. The more significant areas requiring the use of management assumptions and estimates relate to:

   • Mineral Resources that are the basis for future potential income and cash flow estimates;

   • Mineral Reserves that are the basis for units-of-production depreciation, depletion, and amortization calculations;

   • Future mine plans, ore grades, throughput, and recoveries;

   • Future metals prices;

   • Future capital and operating costs;

   • Environmental, reclamation, and closure obligations;

   • The Back Forty Project Gold and Silver Stream Agreements with Osisko Bermuda Limited (“Osisko”);

   • Contingent Consideration Liabilities;

   • Permitting and other regulatory considerations;

   • Asset impairments;

   • The valuation of the Company’s investments in equity securities;

   • Asset acquisition accounting, including the valuation of the transaction and related instruments;

   • Future foreign exchange rates, inflation rates, and applicable tax rates; and

   • Deferred tax asset valuation allowance.

   Future estimates and actual results may differ materially from these estimates as a result of using different assumptions or conditions. For additional information, see Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

   
   The Company’s subsidiary, Aquila Resource Inc., may be required to repay a significant amount if it defaults under certain gold and silver stream agreements.
   

   In connection with the Aquila acquisition, the Company acquired Aquila Resource Inc. which had substantial liabilities related to the Gold and Silver Stream Agreements with Osisko (now called OR Royalties Inc.) (the “Osisko Stream Agreements”). Under the Osisko Stream Agreements, Osisko deposited a total of $37.2 million upfront in exchange for a portion of the future gold and silver production from the Back Forty Project. The Osisko Stream Agreements contain customary provisions regarding default and security. In the event that the Company’s subsidiary, Aquila Resource Inc., defaults under the Osisko Stream Agreements, including by failing to acquire the required permits and achieve commercial production by the agreed upon dates, it may be required to repay the deposit plus accumulated interest at a rate agreed with Osisko. If the subsidiary fails to do so, Osisko may elect to enforce its remedies as a secured party and take possession of the assets that comprise the Back Forty Project.

   Gold Resource Corporation

   14

   The Company’s revenues are concentrated among a select few customers. Any interruption in the Company’s relationship with such customers could materially affect the Company’s operating results.
   

   During the year ended December 31, 2025, two customers accounted for 99% of the Company’s revenue from DDGM. In the event that the Company’s relationship with any of its customers is interrupted for any reason, the Company believes that it would be able to locate another entity to purchase its products in a timely manner on substantially similar terms. However, any interruption could temporarily disrupt the sale of the Company’s principal products and materially adversely affect its operating results.

   Operational Risks

   The Company’s production is derived from a single operating unit, and any interruptions or stoppages in its mining activities at that operating unit would materially adversely affect revenue.
   

   The Company is dependent on revenues from a single operating unit to fund its operations. Any interruption in the Company’s ability to mine this location, such as a labor strike, natural disaster, or loss of permits would negatively impact its ability to generate revenue following such interruption. Additionally, if the Company is unable to develop additional mines economically, it will eventually deplete the body of mineralized material and will no longer generate cash flow sufficient to fund its operations. A decrease in, or cessation of, the Company’s mining operations at this operating unit would materially adversely affect its financial performance and may eventually cause the Company to cease operations.

   Since the Company’s current property portfolio is limited to one operating unit, its ability to be profitable over the long-term will depend on the Company’s ability to (1) expand the known Arista, Switchback and Three Sisters vein systems and /or identify, explore, and develop additional properties in Mexico, (2) successfully develop the Back Forty Project in Michigan, USA, or (3) acquire and develop an alternative project.
   

   Gold and silver producers must continually replace reserves depleted by production to maintain production levels over the long-term and provide a return on invested capital. Depleted reserves can be replaced in several ways, including expanding known ore bodies, locating new deposits, or acquiring interests in reserves from third parties. Exploration is highly speculative in nature, capital intensive, involves many risks, and frequently unproductive. The Company’s current or future exploration programs may not result in new mineralization. Even if significant mineralization is discovered, it will likely take many years from the initial phases of exploration until commencement of production, during which time the economic feasibility of production may change.

   From time to time, the Company may acquire mineral interests from other parties. Such acquisitions are based on an analysis of a variety of factors, including historical exploration results, estimates and assumptions regarding the extent of mineralized material and/or reserves, the timing of production from such reserves, and cash and other operating costs. In addition, the Company may rely on data and reports prepared by third parties, which may contain information or data that the Company would be unable to independently verify or confirm. All of these factors are uncertain and may impact the Company’s ability to develop the mineral interests.

   As a result of these uncertainties, the Company’s exploration programs and any acquisitions which it may pursue may not result in the expansion or replacement of its current production with new ore reserves or operations, which could have a material adverse effect on the Company’s business, prospects, results of operations, and financial position.

   Gold Resource Corporation

   15

   Increasing operating and capital costs may materially adversely impact the Company’s results of operations.
   

   Costs at the Company’s mining properties are subject to fluctuation due to a number of factors, such as variable ore grade, changing metallurgy, and revisions to mine plans in response to the physical shape and location of the ore body, as well as the age and utilization rates for the mining and processing-related facilities and equipment. In addition, costs are affected by the price and availability of input commodities, such as fuel, electricity, labor, chemical reagents, explosives, steel, concrete, and mining and processing related equipment and facilities. Commodity costs are often subject to volatile price movements, including increases that could make mineral extraction less profitable. Further, changes in laws and regulations can affect commodity prices, uses, and transport. Reported costs may also be affected by changes in accounting standards. Increases in costs materially adversely impacted the Company’s results of operations and operating cash flow in the past and may continue to do so in the future.

   The Company could have significant increases in capital and operating costs over the next several years in connection with developing new projects in challenging jurisdictions and sustaining and/or expanding existing mining and processing operations. Costs associated with capital expenditures may increase in the future as a result of factors beyond the Company’s control, such as inflation. Increased capital expenditures may have an adverse effect on the results of operations and cash flow generated from existing operations, as well as the economic returns anticipated from new projects, or may make the development of future projects uneconomic.

   Competition in the mining industry is intense, and the Company has limited financial and personnel resources with which to compete.
   

   In the mining industry, competition for desirable properties, investment capital, and human capital is intense. Numerous companies headquartered in the United States, Canada, and worldwide compete for properties and human capital on a global basis. The Company is a small participant in the mining industry due to its limited financial and human capital resources. The Company presently operates with a limited number of people, and it anticipates operating in the same manner going forward. The Company competes with other companies in its industry to hire qualified employees and consultants when needed to operate its mines successfully and to advance its exploration properties. The Company may be unable to attract the necessary human capital to fully explore, and if warranted, develop its properties and be unable to acquire other desirable properties. The Company believes that competition for acquiring mineral properties, as well as the competition to attract and retain qualified human capital, will continue to be intense in the future.

   Estimates of Proven and Probable Mineral Reserves and Measured and Indicated Mineral Resources include some uncertainty, such that the volume and grade of ore actually recovered may vary from the Company’s estimates.
   

   The Proven and Probable Mineral Reserves stated in this report represent the amount of gold, silver, copper, lead, and zinc that the Company estimated at December 31, 2025 that could be economically and legally extracted or produced at the time of the reserve determination. Estimates of Proven and Probable Mineral Reserves and Measured and Indicated Mineral Resources are subject to considerable uncertainty. Such estimates are largely based on the prices of gold, silver, copper, lead, and zinc, as well as interpretations of geologic data obtained from drill holes and other exploration techniques. These prices and interpretations are subject to change. If the Company determines that certain estimated Mineral Reserves or Mineral Resources have become uneconomic, it may be forced to reduce its estimates. Actual production from Proven and Probable Mineral Reserves may be significantly less than the Company expects. There can be no assurance that estimates of Mineral Resources will be upgraded to Mineral Reserves or may ultimately be extracted.

   Any material changes in Mineral Resources and Mineral Reserves estimates and grades of mineralization may affect the economic viability of the Company’s current operations, a decision to place a new property into production, and/or such property’s return on capital. There can be no assurance that mineral recoveries in small-scale laboratory tests will be duplicated in a large-scale on-site operation in a production environment. Declines in market prices for contained metals may render portions of the Company’s Mineral Resources and Mineral Reserves estimates uneconomic and result in reduced reported mineralization or materially adversely affect the commercial viability of one or more of the Company’s

   Gold Resource Corporation

   16

   properties. Any material reductions in estimates of mineralization, or of the Company’s ability to extract this mineralization, could have a material adverse effect on its results of operations or financial condition.

   Products processed from the Company’s operating mines or other mines in the future could contain higher than expected contaminants, thereby negatively impacting the Company’s financial condition.
   

   Contracts for treatment charges paid to smelters and refineries include penalties for certain deleterious elements that exceed contract limits. If the material mined from the Company’s operating mines includes higher than expected contaminants, the Company would incur higher treatment expenses and penalty charges that could increase costs and negatively impact the business, financial condition, and results of operations. This could occur due to unexpected variations in the occurrence of these elements in the material mined, problems occurring during blending of material from various locations in the mine prior to processing, and other unanticipated events.

   Continuation of the Company’s mining and processing activities is dependent on the availability of sufficient water supplies to support its mining activities.
   

   Water is critical to the Company’s business, and the increasing pressure on water resources requires the Company to consider both current and future conditions in its management approach. Across the globe, water is a shared and regulated resource. Mining operations require significant quantities of water for mining, ore processing, and related support facilities. Many of the Company’s properties in Mexico are in areas where water is scarce, and competition among users for continuing access to water is significant. Continuous production and mine development depend on the Company’s ability to acquire and maintain water rights and defeat claims adverse to current water use in legal proceedings. Although the Company believes that its operations currently have sufficient water rights and claims to cover operating demands, it cannot predict the potential outcome of future legal proceedings relating to water rights, claims, and uses. Water shortages may also result from weather or environmental and climate impacts beyond the Company’s control. Shortages in water supply could result in production and processing interruptions. In addition, the scarcity of water in certain regions could result in increased costs to obtain sufficient quantities of water to conduct the Company’s operations. The loss of some or all water rights, in whole or in part, ongoing shortages of water to which the Company has rights, or significantly higher costs to obtain sufficient quantities of water (or the failure to procure sufficient quantities of water) could result in the Company’s inability to maintain mineral extraction at current or expected levels, require the Company to curtail or shut down mining operations, and prevent it from pursuing expansion or any development opportunities. Laws and regulations may be introduced in some jurisdictions where the Company operates, which could also limit access to sufficient water resources, thus materially adversely affecting its operations.

   The nature of mineral exploration, mining, and processing activities involves significant hazards, a high degree of risk, and the possibility of uninsured losses.
   

   Exploration for and the production of minerals is highly speculative and involves greater risk than many other businesses. Many exploration programs do not result in the discovery of mineralization, and any mineralization discovered may not be of sufficient quantity or quality to be profitably mined. The Company’s operations are, and any future mining operations or construction that may be conducted will be, subject to all of the operating hazards and risks normally incident to exploring for and mining of mineral properties, such as, but not limited to:

   • Fluctuation in production costs that make mining uneconomic;

   • Fluctuation in commodity prices;

   • Social, community, or labor force disputes resulting in work stoppages or delays, or related loss of social acceptance of community support;

   • Changes to legal and regulatory requirements;

   • Unanticipated variations in grade and other geologic problems;

   • Environmental hazards, noxious fumes, and gases;

   • Ground and water conditions;

     Gold Resource Corporation

     17

   • Difficult surface or underground conditions;

   • Industrial accidents;

   • Security incidents;

   • Failure of unproven or evolving technologies or loss of information integrity or data;

   • Metallurgical and other processing problems;

   • Mechanical and equipment performance problems;

   • Failure of pit walls, dams, declines, drifts, and shafts;

   • Unusual or unexpected rock formations;

   • Personal injury;

   • Pandemics, tariffs, and wars that could affect input costs and revenues;

   • Fire, flooding, cave-ins, seismic activity, landslides, or other inclement weather conditions, including those impacting operations or the ability to access and supply sites; and

   • Decrease in the value of mineralized material due to lower gold, silver, and metal prices.

     These occurrences could result in damage to-or destruction of-mineral properties, processing facilities, and equipment; personal injury or death; environmental damage; reduced extraction and processing; delays in mining; asset write-downs; monetary losses; and possible legal liability. Although the Company maintains insurance in amounts that it considers reasonable for general commercial liability claims, physical assets at its Arista and Alta Gracia Mines, and risks inherent in the conduct of its business, this insurance contains exclusions and limitations on coverage and will not cover all potential risks associated with mining and exploration activities. As such, the related liabilities might exceed policy limits. As a result of any or all of the foregoing, the Company could incur significant liabilities and costs that may exceed the limits of its insurance coverage or that it may elect not to insure against because of unreasonable premium costs or other reasons, which could materially adversely affect its results of operations and financial condition. The Company may also not be insured against all interruptions to its operations. Losses from these or other events may cause the Company to incur significant costs which could materially adversely affect its financial condition and its ability to fund activities on its properties. A significant loss could force the Company to reduce or suspend its operations and development.

     Revenue from the sale of metal concentrate may be materially adversely affected by loss or damage during shipment and storage at the Company’s buyer’s facilities.
     

     The Company relies on third-party transportation companies to transport its metal concentrate to each buyer’s facilities for processing and further refining. The terms of the Company’s sales contracts with the buyers require the Company to rely, in part, on assay results from samples of its metal concentrate that are obtained at the buyer’s warehouse to determine the final sales value for metals. Once the metal concentrate leaves the processing facility, the Company no longer have direct custody and control of these products. Theft, loss, road accidents, improper storage, fire, natural disasters, tampering, or other unexpected events while in transit or at the buyer’s location may lead to the loss of all or a portion of the Company’s metal concentrate products. Such losses may not be covered by insurance and may lead to a delay or interruption in revenue, and as a result, the Company’s operating results may be materially adversely affected.

     A significant delay or disruption in sales of doré or concentrates as a result of the unexpected disruption in services provided by smelters or refiners could have a material adverse effect on results of operations.
     

     The Company relies on third-party smelters and refiners to refine and process and, in some cases, purchase, the gold and silver doré and copper, lead, and zinc concentrate produced from its mines. Access to smelters and refiners on economic terms is critical to the Company’s ability to sell its products to buyers and generate revenues. The Company periodically enters into agreements with smelters and refiners, some of which operate their smelting or refining facilities outside the United States, and it believes it currently has contractual arrangements with a sufficient number of smelters and refiners so that the loss of any one refiner or smelter would not significantly or materially impact the Company’s operations or its ability to generate revenues. Nevertheless, services provided by a refiner or smelter may be disrupted by operational issues; new or increased tariffs, duties, or other cross-border trade barriers; the bankruptcy or insolvency of one or more smelters or refiners; or the inability to agree on acceptable commercial or legal terms with a refiner or smelter.

     Gold Resource Corporation

     18

     Such an event or events may disrupt an existing relationship with a refiner or smelter or result in the inability to create a contractual relationship with a refiner or smelter, which may leave the Company with limited, uneconomical, or no access to smelting or refining services for short or long periods of time. Any such delay or loss of access may significantly impact the Company’s ability to sell doré and concentrate products. The Company cannot ensure that alternative smelters or refiners would be available or offer comparable terms if the need for them arose or that it would not experience delays or disruptions in sales that would materially adversely affect the results of operations.

     The Company relies on contractors to conduct a significant portion of the Company’s exploration, development, and construction projects.
     

     A significant portion of the Company’s development and construction projects are currently conducted in whole or in part by contractors. As a result, the Company’s operations are subject to a number of risks, some of which are outside of its control, including:

   • Negotiating agreements with contractors on acceptable terms;

   • New foreign or domestic legislation limiting or altering the ability to utilize contractors or outsourced resources;

   • The difficulty and inherent delay in replacing a contractor and its equipment in the event that either party terminates the agreement;

   • Reduced control and oversight over those aspects of the work which are the responsibility of the contractor;

   • Failure of a contractor to perform under its agreement;

   • Interruption of development and construction or increased costs in the event that a contractor ceases its business due to insolvency or other unforeseen events;

   • Injuries or fatalities on the job as a result of the failure to implement or follow adequate safety measures;

   • Failure of a contractor to comply with applicable legal and regulatory requirements, to the extent it is responsible for such compliance; and

   • Problems of a contractor managing its workforce, labor unrest, or other related employment issues.

     In addition, the Company may incur liability to third parties as a result of the actions of its contractors. The occurrence of one or more of these risks could materially adversely affect the Company’s results of operations and financial position.

     Gold Resource Corporation

     19

     Risks Related to the Company’s Exploration Activities

     The exploration of the Company’s mineral properties is highly speculative in nature, involves substantial expenditures, and is frequently non-productive.
     

     Mineral exploration is highly speculative in nature and frequently results in no or very little return on amounts invested in evaluating a particular property. The probability of an individual prospect ever having Mineral Reserves that meets the requirements of Subpart 1300 of Regulation S-K (“S-K 1300”) is low. Even if the Company does eventually discover Mineral Resources and Mineral Reserves on its exploration properties, there can be no assurance that it can develop a mine and extract those minerals. Substantial expenditures are required to (i) establish the existence of a potential ore body through drilling and metallurgical and other testing techniques; (ii) determine metal content and metallurgical recovery processes to process metal from the ore; (iii) determine the feasibility of mine development and production; and

     (iv) construct, renovate, or expand mining and processing facilities. If the Company discovers a deposit or ore at a property, it usually takes several years from the initial phases of exploration until mineral extraction is possible, if at all. During this time, the economic feasibility of a project may change because of increased costs, lower metal prices, or other factors. As a result of these uncertainties, the Company’s exploration programs may not result in the identification of proven and probable Mineral Reserves in sufficient quantities to justify developing a particular property.

     The Company has acquired and may in the future acquire additional mining properties, and the Company’s business may be negatively impacted if Mineral Resources and Mineral Reserves are not located on acquired properties or if it is unable to successfully execute and/or integrate the acquisitions as planned.
     

     The Company has in the past, and may in the future, acquire additional mining properties. There can be no assurance that reserves will be identified on any properties that it acquires. The Company may experience negative impacts on the trading price of its common stock or on its ability to access capital if it successfully completes acquisitions of additional properties and reserves are not located on these properties.

     In December 2021, the Company acquired the Back Forty Project when it purchased Aquila. The acquisition may result in various material adverse impacts on the Company’s business and the trading price of its common stock. Adverse impacts may include, without limitation, the risk that the acquisition does not achieve the expected benefits, increased cash outflows, the unavailability of capital to develop the Back Forty Project, and the risk of potential material adverse tax consequences for the Company and its shareholders. Additional risks, difficulties, and uncertainties may result from the separation of previously co-mingled businesses, including necessary ongoing relationships. While the Company has invested significant time, money, and equity in acquiring the Back Forty Project, there can be no assurance that the Back Forty Project will be permitted or will ultimately be productive.

     The success of any future acquisition would depend on a number of factors, including, but not limited to:

   • Identifying suitable candidates for acquisition and negotiating acceptable terms;

   • Obtaining approval from regulatory authorities and potentially the Company’s shareholders;

   • Implementing the Company’s standards, controls, procedures, and policies at the acquired business and addressing any pre-existing liabilities or claims involving the acquired business; and

   • To the extent the acquired operations are in a country where the Company has not operated historically, understanding the regulations and challenges of operating in that new jurisdiction.

   There can be no assurance that the Company will be able to successfully conclude any acquisitions, or that any acquisition will achieve the anticipated synergies or other anticipated positive results. Any material problems that the Company encounters in connection with such an acquisition could have a material adverse effect on its business, results

   Gold Resource Corporation

   20

   of operations, and financial position. These factors may materially adversely affect the trading price of the Company’s common stock.

   Regulatory and Geopolitical Risks

   The Company’s operations are subject to ongoing permitting requirements, which could result in the delay, suspension, or termination of its operations.
   

   The Company’s operations, including ongoing exploration drilling programs and mining, require ongoing permits from governmental and local authorities. The Company may also be required to obtain certain property rights to access or use its properties. Obtaining or renewing licenses and permits and acquiring property rights can be complex and time-consuming processes. There can be no assurance that the Company will be able to acquire all required licenses, permits, or property rights on reasonable terms or in a timely manner, or at all, and that such terms will not be adversely changed; that required extensions will be granted; or that the issuance of such licenses, permits or property rights will not be challenged by third parties. If the Company cannot obtain or maintain the necessary permits, or if there is a delay in receiving future permits, its timetable and business plan will be materially adversely affected.

   The Company’s operating properties located in Mexico are subject to changes in political or economic conditions and regulations in that country.
   

   The risks with respect to operating in Mexico or other developing countries include, but are not limited to, nationalization of properties, military repression, extreme fluctuations in currency exchange rates, increased security risks, labor instability or militancy, mineral title irregularities, and high rates of inflation. Furthermore, the Company’s operations in Mexico may be subject to increased political and security risks stemming from civic unrest. Incidents of high-profile civic unrest-including cartel-related violence, extortion, and threats to personnel and infrastructure-could disrupt operations, increase security-related expenditures, and pose risks to the safety of employees and contractors.

   Changes in mining or investment policies or shifts in political attitudes in Mexico may also materially adversely affect the Company’s business. The Company may be affected in varying degrees by government regulation concerning restrictions on production, price controls, export controls, income taxes, expropriation of property, maintenance of claims, environmental legislation, land use, land claims of local people, opposition from non-governmental organizations, labor legislation, water use, and mine safety. The effect of these factors cannot be accurately predicted and may adversely impact the Company’s operations.

   Most of the Company’s properties are subject to extensive environmental laws and regulations, which could materially adversely affect its business.
   

   The Company’s exploration and mining operations are subject to extensive laws and regulations governing land use and the protection of the environment, which control the exploration and mining of mineral properties and their effects on the environment, including air and water quality, mine reclamation, waste generation, handling and disposal, the protection of different species of flora and fauna, and the preservation of lands. These laws and regulations require the Company to acquire permits and other authorizations for conducting certain activities. In many countries, there is relatively new comprehensive environmental legislation, and the permitting and the authorization process may not be established or predictable. The Company may not be able to acquire necessary permits or authorizations on a timely basis, if at all. Delays in acquiring any permit or authorization could increase the cost of the Company’s projects and could suspend or delay the commencement of extraction and processing of mineralized material.

   Environmental legislation in Mexico and in many other countries is evolving in a manner that will require stricter standards and enforcement, increased fines and penalties for non-compliance, more stringent environmental assessments of proposed projects, and a heightened degree of responsibility for companies and their officers, directors, and employees. Future changes in environmental regulation in the jurisdictions where the Company’s properties are located may materially adversely affect its business, make the business prohibitively expensive, or prohibit it altogether. The Company cannot predict what environmental legislation or regulations will be enacted or adopted in the future or how future laws and

   Gold Resource Corporation

   21

   regulations will be administered or interpreted. Compliance with more stringent laws and regulations, as well as potentially more vigorous enforcement policies, stronger regulatory agencies, or stricter interpretation of existing laws, may

   (i) necessitate significant capital outlays, (ii) cause the Company to delay, terminate, or otherwise change its intended activities with respect to one or more projects, or (iii) materially adversely affect future exploration activities.

   Climate change and climate change legislation or regulations could impact the Company’s business.
   

   The Company is subject to physical risks associated with climate change, which could seriously harm its results of operations and increase costs and expenses. The occurrence of severe adverse weather conditions, including increased temperatures and droughts, fires, longer wet or dry seasons, increased precipitation, floods, hail, snow, or more severe storms may have a potentially devastating impact on the Company’s operations. Adverse weather may result in physical damage to operations, instability of the Company’s infrastructure and equipment, washed-out roads to its properties, and altered water and electricity supply to projects. Increased temperatures may also decrease worker productivity at the Company’s projects and raise ventilation and cooling costs. Changes in the quantity of water, whether in excess or deficient amounts, may impact exploration and development activities, mining and processing operations, water storage and treatment facilities, tailings storage facilities, closure and reclamation efforts, and may increase levels of dust in dry conditions, and land erosion and slope stability in case of prolonged wet conditions. Should the impacts of climate change be material in nature or occur for lengthy periods of time in the areas in which the Company operates, financial condition or results of operations could be materially adversely affected.

   The Company’s continuing reclamation obligations at its operations could require significant additional expenditure.

   The Company is responsible for the reclamation obligations related to disturbances located on all of its properties and have recorded a liability on its Consolidated Balance Sheets to cover the estimated reclamation obligation. However, there is a risk that any reserve could be inadequate to cover the actual costs of reclamation when carried out. Continuing reclamation obligations will require a significant amount of capital. There is a risk that the Company will be unable to fund these obligations and that the regulatory authorities may increase reclamation requirements to such a degree that it would not be commercially reasonable to continue mining and exploration activities, which may materially adversely affect results of operations, financial performance, and cash flows.

   The Company’s ability to develop its Mexican properties is subject to the rights of the Ejido (agrarian cooperatives), and violations of such rights could result in the Company’s loss of title in the subject properties, which would have a materially adverse effect on the Company’s business and financials.
   

   Mining concessions in Mexico give exclusive exploration and exploitation rights to the minerals located in the concessions but do not include surface rights to the real property, which requires that the Company negotiates the necessary agreements with surface landowners. Many of the mining properties are subject to the Mexican Ejido system, which are groups of local inhabitants who were granted rights to conduct agricultural activities on the property, for access and surface disturbances, requiring the Company to contract with the local communities surrounding the properties in order to obtain surface rights to land needed in connection with mining exploration activities. The Company’s ability to mine minerals is subject to maintaining satisfactory arrangements and relationships with the Ejido.

   The Company must negotiate and maintain a satisfactory arrangement with these residents in order to disturb or discontinue their rights to farm. While the Company has successfully negotiated and signed such agreements related to the DDGM operations, its inability to maintain these agreements or consummate similar agreements for new projects could impair or impede the ability to successfully explore, develop, and mine the properties, which in turn could materially adversely affect the Company’s future cash flow.

   In February 2020, a local Ejido community (who claim to be an indigenous community) filed an injunction against the Mexican federal government alleging failure to conduct a prior consultation before granting mining concessions and seeking cancellation of several concessions, including certain concessions granted to DDGM. A federal suspension was issued in February 2020 prohibiting certain mining activities on the named concessions. DDGM’s operations are conducted

   Gold Resource Corporation

   22

   on a concession that was not part of the original lawsuit, and DDGM does not presently perform such works in the concessions in lands of the indigenous community named in the injunction. The lawsuit is filed with the First District Courthouse in the state of Oaxaca and the case remains pending. If the lawsuit is successful, affected concessions, including the concession where DDGM currently operates, could be cancelled, and the Company would need to complete a consultation process and reapply for the concessions, which would have a materially adverse effect on its operations and financial condition. Please see Item 1A. Risk Factors-Regulatory Risks-Title to mineral properties can be uncertain and disputes regarding the title to the Company’s Mexican properties require the Company to litigate such disputes in Mexico, where it faces unfamiliar laws and procedures.

   Title to mineral properties can be uncertain and disputes regarding the title to the Company’s Mexican properties require the Company to litigate such disputes in Mexico, where it faces unfamiliar laws and procedures.
   

   The Company’s ability to explore and operate its properties depends on the validity of its title to that property. Uncertainties inherent in mineral properties relate to such things as the sufficiency of mineral discovery, proper posting and marking of boundaries, assessment work and possible conflicts with other claims not determinable from public record. There may be valid challenges to the title to the Company’s properties which, if successful, could impair development and/or operations. The resolution of disputes in foreign countries can be costly and time consuming. In a foreign country, the Company faces the additional burden of understanding unfamiliar laws and procedures. Not like in the U.S., the Company may not be entitled to a jury trial. Further, to litigate in Mexico, the Company is faced with the necessity of hiring lawyers and other professionals who are familiar with the Mexican laws. For these reasons, the Company may incur additional unforeseen costs to resolve its disputes in Mexico.

   Under the laws of Mexico, Mineral Resources belong to the United States of Mexico, and government concessions are required to explore for or exploit Mineral Reserves. Mineral rights derive from concessions granted-on a discretionary basis-by the Ministry of Economy, pursuant to the Mexican mining law and regulations thereunder. Additionally, in 2014, new mining concessions became subject to additional review and approval by the Mexico Ministry of Energy, and in recent years, the federal government has been reluctant to issue new mining concessions.

   The Company’s concessions in Mexico are subject to continuing government regulation, and failure to adhere to such regulations will result in the termination of such concessions. A title defect could result in losing all or a portion of the Company’s right, title, and interest in and to the properties to which the title defect relates. Furthermore, failure to comply with applicable laws and regulations relating to mineral right applications and tenure could result in loss, reduction or expropriation of entitlements, or the imposition of additional local or foreign parties as joint venture partners. Any such loss, reduction, or imposition of partners could have a material adverse effect on the Company’s financial condition, results of operations, and prospects.

   A significant amount of the Company’s mining properties are subject to exchange control policies, the effects of inflation, and currency fluctuations between the U.S. dollar and the Mexican peso.
   

   The Company’s revenue and external funding are primarily denominated in U.S. dollars. However, certain mining, processing, maintenance, and exploration costs are denominated in Mexican pesos. These costs principally include electricity, labor, water, maintenance, local contractors, and fuel. The appreciation of the peso against the U.S. dollar increases expenses and the cost of purchasing capital assets in U.S. dollar terms in Mexico, which can adversely impact the Company’s operating results and cash flows. Conversely, the depreciation of the Mexican peso decreases operating costs and capital asset purchases in U.S. dollar terms. When inflation in Mexico increases without a corresponding devaluation of the Mexican peso, the Company’s financial position, results of operations, and cash flows could be materially adversely affected. The annual average inflation rate in Mexico was approximately 3.82% in 2025 and 4.72% in 2024. Current and future inflationary effects may be driven by, among other things, supply chain disruptions, governmental stimulus or fiscal policies, and geopolitical instability. For additional information, please see Item 1A. Risk Factors-General Risks- Global and regional political and economic conditions could adversely impact the Company’s business. Continuing increases in inflation could increase the costs of labor and other costs related to the business, which could have an adverse impact on the Company’s business, financial position, results of operations, and cash flows.

   Gold Resource Corporation

   23

   At the same time, the peso has been subject to fluctuation, which may not have been proportionate to the inflation rate and may not be proportional to the inflation rate in the future. The value of the peso increased by 12.8% in 2025 and decreased by 16.7% in 2024. In addition, fluctuations in currency exchange rates may have a significant impact on the Company’s financial results. There can be no assurance that the Mexican government will maintain its current policies with regard to the peso or that the peso’s value will not fluctuate significantly in the future. The Company cannot assure you that currency fluctuations, inflation, and exchange control policies will not have an adverse impact on its financial condition, results of operations, earnings, and cash flows.

   Lack of infrastructure could forestall or prevent further exploration and advancement.
   

   Exploration activities, as well as any advancement activities, depend on adequate infrastructure. Reliable roads, bridges, power sources, and water supply are important factors that affect capital and operating costs and the feasibility and economic viability of a project. Unanticipated or higher than expected costs and unusual or infrequent weather phenomena, or government or other interference in the maintenance or provision of such infrastructure, could materially adversely affect the Company’s business, financial condition, and results of operations.

   Risks Related to the Company’s Common Stock

   Volatility in the Company’s stock price could result in shareholders losing part or all of their investment.
   

   In addition to other risk factors identified in this annual report on Form 10-K, and due to volatility associated with equity securities in general, the value of a shareholder’s investment could decline due to the impact of numerous factors upon the market price of the Company’s common stock, including divergence between its actual or anticipated financial results and published expectations of analysts or the expectations of the market, the gain or loss of customers, announcements that the Company, its competitors or its customers may make regarding their operating results and other factors that are beyond the Company’s control, such as market conditions in the Company’s or its customers’ industry, new market entrants, technological innovations, and economic and political conditions or events.

   Stock markets in general have experienced extreme price and volume fluctuations, and the market prices of individual securities have been highly volatile. These fluctuations are often unrelated to operating performance and may materially adversely affect the market price of the Company’s common stock. As a result, shareholders may be unable to sell their shares at a desired price.

   Past payments of dividends on the Company’s common stock are not a guaranty of future payments of dividends.
   

   In 2010, the Company began paying cash dividends to the holders of its common stock, but in February 2023, in order to conserve cash for future development and exploration, the Company announced the suspension of quarterly dividends. The Company’s ability to pay dividends in the future will depend on a number of factors, including free cash flow, expected operational performance, mine construction requirements and strategies, other acquisition and/or construction projects, spot metal prices, taxation, government-imposed royalties, and general market conditions. Further, a portion of the Company’s cash flow is expected to be retained to finance operations, explorations, and development of mineral properties. There is no assurance that the Board will elect to re-institute a dividend payment in the near-term or at all.

   Issuances of the Company’s stock in the future could dilute existing shareholders and materially adversely affect the market price of its common stock.
   

   The Company has the authority to issue up to 200,000,000 shares of common stock, 5,000,000 shares of preferred stock, and to issue options and warrants to purchase shares of its common stock, in some cases without shareholder approval. As of March 16, 2026, there were 161,858,849 shares of common stock outstanding. Future issuances of the Company’s securities could be at prices substantially below the price paid for its common stock by current shareholders. The Company can issue significant blocks of its common stock without further shareholder approval. Because the

   Gold Resource Corporation

   24

   Company has issued less common stock than many of its larger peers, the issuance of a significant amount of common stock may have a disproportionately large impact on share price compared to larger companies.

   General Risks

   The failure to complete our announced Transaction with Goldgroup could have a material adverse effect on our business, results of operations, financial condition, cash flows and stock price.
   

   On January 26, 2026, the Company announced that it entered into the Arrangement Agreement with Goldgroup, whereby Goldgroup has agreed to acquire all of the issued and outstanding shares of the Company’s common stock. The proposed Transaction will occur by way of a reverse triangular merger in which the Company will merge with a wholly owned subsidiary of Goldgroup under Colorado law and a plan of arrangement under the Business Corporations Act (British Columbia), with the Company surviving as a wholly owned subsidiary of Goldgroup. The Transaction is expected to close in the second quarter of 2026, subject to customary closing conditions (including approval by the stockholders of each of the Company and Goldgroup and approval by the Mexican National Antitrust Commission). There is no assurance that all of the conditions of the Arrangement Agreement will be satisfied, or that the Transaction will be completed on the announced terms, within the expected timeframe or at all. The closing of the Transaction may be delayed, or the Transaction may not be completed, due to a number of factors, including as a result of the failure to obtain regulatory approval or to satisfy any other requisite closing conditions.

   If the Transaction does not close, the Company could suffer consequences that may have an adverse effect on its business, financial condition, operating results, cash flows and stock price. To the extent that the market price of the Company’s common stock reflects the assumption that the Transaction will be completed in the second quarter of 2026 or at all, the price of our stock could decline. The Company may experience adverse effects or changes to relationships with customers, employees, suppliers or other parties resulting from the failure to complete the Transaction. Additionally, there may be potential litigation relating to the Merger that could be instituted against the Company.

   The Company’s operations may be disrupted, and its financial results may be materially adversely affected by any future pandemic.
   

   Any pandemic may pose a risk to the business and operations. If a significant portion of the Company’s workforce becomes unable to work or travel to the operations due to illness or state or federal government restrictions (including travel restrictions and “shelter-in-place” and similar orders restricting certain activities that may be issued or extended by authorities), the Company may be forced to reduce or suspend operations, exploration activities, and/or development projects, which may impact liquidity and financial results. These restrictions have significantly disrupted economic activity in both the world, national, and local economies and have caused volatility in capital markets.

   To the extent any pandemic materially adversely affects the Company’s business and financial results, as discussed above, it may also have the effect of heightening many of the other risks described in this “Risk Factors” section, such as those relating to operation, indebtedness, and financing. The Company is unable to predict the ultimate adverse impact of any pandemic on the business, which will depend on numerous evolving factors and future developments, including the pandemic’s ongoing effect on the demand for silver and gold, as well as the response of the overall economy and the financial markets after the pandemic and response measures come to an end, the timing of which remains highly unpredictable.

   Gold Resource Corporation

   25

   Global and regional political and economic conditions could adversely impact the Company’s business.
   

   Political and economic shifts, both domestic and international, may create uncertainty and pose risks to the Company’s operations. Policies related to populism, protectionism, economic nationalism, and attitudes toward multinational corporations could result in regulatory changes, trade barriers, or investment restrictions. Additionally, international trade disputes-including tariffs, counter-tariffs, export controls, sanctions, and currency regulations-may increase costs and disrupt supply chain, operating model, and customer relationships.

   Further, market volatility, driven by shifts in U.S. and foreign trade policies, fluctuating interest rates, or currency controls may affect gold prices, capital availability, and investor confidence. Even the perception of these risks could lead to reduced investment, higher production costs, and operational challenges. If such trends continue, they may have a material adverse effect on the business and financial performance.

   The Company may not be able to operate successfully if it is unable to recruit, hire, retain, and develop key personnel and maintain a qualified and diverse workforce. In addition, the Company is dependent upon its employees being able to safely perform their jobs, but there is risk of physical injuries or illness.
   

   The Company depends upon the services of a number of key executives and management personnel. These individuals include executive officers and other key employees. If any of these individuals were to die, become disabled, or leave the Company, the Company would be forced to identify and retain individuals to replace them but may be unable to hire a suitable replacement on favorable terms should that become necessary.

   The Company’s success is also dependent on the contributions of its highly skilled and experienced workforce. The Company’s ability to achieve its operating goals depend upon the ability to recruit, hire, retain, and develop qualified and diverse personnel to execute on its strategy. There continues to be competition over highly skilled personnel in the industry. If the Company loses key personnel or one or more members of senior management team; or if it fails to develop adequate succession plans; or if it fails to hire, retain, and develop qualified and diverse employees; the business, financial condition, results of operations, and cash flows could be harmed.

   The Company is dependent on information technology systems, which are subject to certain risks, including cybersecurity risks, data leakage risks, and risks associated with implementation and integration.
   

   The Company is dependent upon information technology systems in the conduct of its business. Any significant breakdown, invasion, virus, cyberattack, security breach, destruction, or interruption of these systems by employees, others with authorized access to its systems, or unauthorized persons could negatively impact the business. To the extent any invasion, cyberattack, or security breach results in disruption to the business, such as loss or disclosure of, or damage to data or confidential information; business reputation, results of operations, and financial condition could be materially adversely affected. The Company has implemented various measures to manage the risks related to information technology systems and network disruptions. However, given the unpredictability of the timing, nature, and scope of information technology disruptions, the Company could potentially be subject to production downtimes, operational delays, the compromising of confidential or otherwise protected information, destruction or corruption of data, security breaches, other manipulation or improper use of its systems, and networks or financial losses from remedial actions, any of which could have a material adverse effect on cash flows, competitive position, financial condition, or results of operations. The Company’s systems and insurance coverage for protecting against cyber security risks may not be sufficient. Although to date the Company has not experienced any material losses relating to cyberattacks, it may suffer such losses in the future. The Company may be required to expend significant additional resources to continue to modify or enhance protective measures. The Company also may be subject to significant litigation, regulatory investigation, and remediation costs associated with any information security vulnerabilities, cyberattacks, or security breaches.

   The Company may also be materially adversely affected by system or network disruptions if new or upgraded information technology systems are defective, not installed properly, or not properly integrated into its operations. If the

   Gold Resource Corporation

   26

   Company is unable to successfully implement system upgrades or modifications, it may have to rely on manual reporting processes and controls over financial reporting that have not been planned, designed, or tested. Various measures have been implemented to manage the risks related to the system upgrades and modifications, but system upgrades and modification failures could have a material adverse effect on the business, financial condition, and results of operations and could, if not successfully implemented, adversely impact the effectiveness of internal controls over financial reporting.

   The Company’s business is subject to the U.S. Foreign Corrupt Practices Act and similar worldwide anti-bribery laws, a breach or violation of which could lead to civil and criminal fines and penalties, loss of licenses or permits, and reputational harm.
   

   The Company operates in certain jurisdictions that have experienced some degree of governmental and private sector corruption, and in certain circumstances, strict compliance with anti-bribery laws may conflict with certain local customs and practices. The U.S. Foreign Corrupt Practices Act and anti-bribery laws in other jurisdictions generally prohibit companies and their intermediaries from making improper payments for the purpose of obtaining or retaining business or other commercial advantages. The Company’s Code of Ethics and other corporate governance mandate compliance with these anti-bribery laws, which often carry substantial penalties. However, there can be no assurance that internal control policies and procedures will always protect the Company from recklessness, fraudulent behavior, dishonesty, or other inappropriate acts committed by affiliates, employees, contractors, or agents. As such, the corporate policies and processes may not prevent all potential breaches of law or other governance practices. Violations of these laws, or allegations of such violations, could lead to civil and criminal fines and penalties, litigation, loss of operating licenses or permits, and may damage the Company’s reputation, which could have a material adverse effect on the business, financial position, and results of operations, or cause the market value of common stock to decline.

   ‌ITEM 1B. UNRESOLVED STAFF COMMENTS

   None.

   ‌ITEM 1C. CYBERSECURITY

   Risk Management and Strategy

   The Company has established policies and processes for assessing, identifying, and managing material risk from cybersecurity threats and have integrated these processes into its overall risk management systems and processes. The Company routinely assesses material risks from cybersecurity threats, including any potential unauthorized occurrence on or conducted through its information systems that may result in adverse effects on the confidentiality, integrity, or availability of information systems or any information residing therein.

   The Company conducts periodic risk assessments to identify cybersecurity threats, as well as assessments in the event of a material change in business practices that may affect information systems that are vulnerable to such cybersecurity threats. These risk assessments include identification of reasonably foreseeable internal and external risks, the likelihood and potential damage that could result from such risks, and the sufficiency of existing policies, procedures, systems, and safeguards in place to manage such risks.

   Governance

   One of the key functions of the Board is informed oversight of the risk management process, including risks from cybersecurity threats. The Board is responsible for monitoring and assessing strategic risk exposure, and management is responsible for the day-to-day management of any material risks that may arise. The Board receives periodic updates from management regarding cybersecurity matters and is notified between such updates regarding any significant new cybersecurity threats or incidents. The Company does not believe that there are currently any known risks from cybersecurity threats that are reasonably likely to materially affect it or its business strategy, results of operations, or financial condition. For more information regarding the expertise of the Board as it relates to cybersecurity, see the section

   Gold Resource Corporation

   27

   entitled “Governance” in the Company’s definitive proxy statement relating to the 2025 Annual Meeting of Stockholders filed with the SEC on April 25, 2025.

   Management is responsible for the operational oversight of company-wide cybersecurity strategy, policy, and standards across relevant departments to assess and help prepare the Company to address cybersecurity risks. As part of the overall risk management system, the Company monitors and tests safeguards and trains employees on these safeguards. Personnel at all levels and departments are made aware of the cybersecurity policies through training.

   Cybersecurity Threats

   As of December 31, 2025, the Company has not identified an indication of a cybersecurity incident that would have a material impact on the Company’s business and consolidated financial statements. For further discussion of cybersecurity risks, please refer to Item 1A. Risk Factors.

   Gold Resource Corporation

   28

   ‌ITEM 2. PROPERTIES

   Glossary.

   The following terms used in this report shall have the following meanings:

   Andesite: An extrusive igneous, volcanic rock, of intermediate composition, with aphanitic to porphyritic texture characteristic of subduction zones, such as the western margin of South America.

   Concentrate: A product from a mineral processing facility, such as gravity separation or flotation, in which the valuable constituents have been upgraded and unwanted gangue materials rejected as waste.

   Cut and Fill: A mining method where ore is removed in horizontal slices, and each mined-out area is backfilled before mining the next level. The fill provides support and a working platform. This method is highly selective and works well in narrow, steep, or irregular ore bodies. Ore is typically loaded and hauled using load, haul, dump machine (“LHD”) equipment.

   Doré: Composite gold and silver bullion, usually consisting of approximately 90% precious metals that will be further refined to separate pure metals.

   Drift: A horizontal tunnel generally driven within or alongside an ore body and aligned parallel to the long dimension of the ore.

   Epithermal: Used to describe gold deposits found on or just below the surface close to vents or volcanoes, formed at low temperature and pressure.

   Exploration: Prospecting, sampling, mapping, diamond-drilling, and other work involved in locating the presence of economic deposits and establishing their nature, shape, and grade.

   Grade: The concentration of an element of interest expressed as relative mass units (percentage, ounces per ton, grams per tonne (“g/t”), etc.).

   Hectare: A metric unit of measurement, for surface area. One hectare equals 1/200th of a square kilometer, 10,000 square meters, or 2.47 acres. A hectare is approximately the size of a soccer field.

   Long-hole Stoping: Mining method which uses holes drilled by a production drill to a predetermined pattern by a mining engineer. Long-hole stoping is a highly selective and productive method of mining and can cater for varying ore thicknesses and dips (0 – 90 degree). Blasted rock is designed to fall into a supported drawpoint or be removed with remote control LHD.

   Net Smelter Return (“NSR”):

   The net revenue that the owner of a mining property receives from the sale of the mine’s metal products, less transportation and refining costs. As a royalty, it refers to the fraction of net smelter return that a mine operator is obligated to pay the owner of the royalty agreement.

   Mineral Deposit: Rocks that contain economic amounts of minerals in them and that are expected to be profitably mined.

   Tonne: A metric ton. One tonne equals 1000 kg. It is equal to approximately 2,204.62 pounds. Volcanogenic: Of volcanic origin.

   Gold Resource Corporation

   29

   Volcanic domes: These are mounds that form when viscous lava erupts slowly and piles up over the vent, rather than moving away as lava flow. The sides of most domes are very steep and typically are mantled with unstable rock debris formed during or shortly after dome emplacement. Most domes are composed of silica-rich lava, which may contain enough pressurized gas to cause explosions during dome extrusion.

   Overview

   The Company classifies its mineral properties into three categories: “Production Stage Properties,” “Development Stage Properties,” and “Exploration Stage Properties.” Production Stage Properties are properties for which the Company operates a producing mine.

   At the Don David Gold Mine, the Company currently has 100% interest in six properties, including two Production Stage Properties and four Exploration Stage Properties, located in Oaxaca, Mexico, along the San Jose structural corridor. Because of their proximity and relatively integrated operations, the Company collectively refers 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 the Company considers to be independently material at this time. Please see Item 2. Properties – Don David Gold Mine for further discussion of the properties.

   The Company also has 100% interest in the Back Forty Project, an advanced Exploration Stage Property, located in Menominee County, Michigan, USA. The Company does not consider the Back Forty Project to be independently material to the Company at this time. Please see Item 2. Properties- Back Forty Project for further discussion of the property.

   Mineral Resources

   Under Regulation S-K 1300, a “Mineral Resource” is defined as a concentration or occurrence of material of economic interest in or on the Earth’s crust in such form, grade or quality, and quantity that there are reasonable prospects for economic extraction. A Mineral Resource is estimated based on geological evidence and sampling and considers relevant factors such as cut-off grade, mining method, mining dimensions, metallurgical recovery, location, and continuity, under assumed and justifiable technical and economic conditions. Mineral Resources do not have demonstrated economic viability.

   Gold Resource Corporation

   30

   The following tables summarize the estimated Mineral Resources at DDGM and at Back Forty:

   Don David Gold Mine – Summary of Gold, Silver, and Base Metal Mineral Resources at December 31, 2025(1)(2)(3)(4)(5)(6)

   
   Description Tonnes

   (k/t)

   
   Gold
   

   (g/t)

   Silver
   

   (g/t)

   Copper
   

   (%)

   Lead
   

   (%)

   Zinc
   

   (%)

   Cut-off grade
   

   Metallurgical Recovery (%)
   

   Arista	$/Tonne							Au	Ag	Cu	Pb	Zn
   Measured Mineral Resources	3	1.40	192.3	0.32	1.04	4.22	150	71.3	85.0	58.9	65.8	76.3
   Indicated Mineral Resources	60	1.66	248.6	0.27	1.78	5.41	150	71.3	85.0	58.9	65.8	76.3
   Measured + Indicated	63	1.65	245.7	0.28	1.74	5.35	150	71.3	85.0	58.9	65.8	76.3
   Inferred Mineral Resources	1,366	0.84	128.0	0.23	1.25	3.69	150	71.3	85.0	58.9	65.8	76.3
   Alta Gracia							AuEq (g/t)
   Measured Mineral Resources	27	0.81	370.6	–	–	–	2.35	85.0	72.0	–	–	–
   Indicated Mineral Resources	141	0.49	270.0	–	–	–	2.35	85.0	72.0	–	–	–
   Measured + Indicated	168	0.54	286.1	–	–	–	2.35	85.0	72.0	–	–	–
   Inferred Mineral Resources	148	0.62	295.6	–	–	–	2.35	85.0	72.0	–	–	–

   Notes on Mineral Resources:

   1. Mineral Resources estimated at December 31, 2025 are based on $3,000/oz for gold, $38.00/oz for silver, $4.54/pound for copper, $0.95/pound for lead and $1.25/pound for zinc. The metal prices used are based on conservative estimates of the average median consensus prices for each of the three years starting in 2026 through 2028 as provided by Bloomberg’s consensus commodity price forecast as at November 21, 2025. The 2028 consensus was used for the remaining life of mine.

   2. The definitions for Mineral Resources in S-K 1300 were followed, which are consistent with definitions outlined by the Canadian Institute of Mining’s Definition Standards for Mineral Resources & Mineral Reserves (“CIM (2014)”) and are exclusive of Mineral Reserves.

   3. The Arista Mine cut-off grade applied to Mineral Resources estimated at December 31, 2025 is $150/tonne NSR.

   4. No appreciable amounts of base metals are present in the Alta Gracia veins identified to date. A breakeven cut-off grade of 2.35 g/t AuEq was used for Mineral Resources using gold and silver only to calculate gold equivalencies.

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

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

For comparison, as at December 31, 2024, DDGM’s estimates of Mineral Resources, exclusive of Mineral Reserves, are provided in the table below.

Don David Gold Mine – Summary of Gold, Silver, and Base Metal Mineral Resources at December 31, 2024(1)(2)(3)(4)(5)(6)

Description Tonnes

(k/t)

Gold

(g/t)

Silver

(g/t)

Copper

(%)

Lead

(%)

Zinc

(%)

Cut-off grade Metallurgical Recovery (%)

Arista							$/Tonne	Au	Ag	Cu	Pb	Zn
Measured Mineral Resources	4	0.54	79.4	0.31	1.35	5.14	120	79.5	91.4	73.9	71.8	83.2
Indicated Mineral Resources	201	1.02	164.5	0.29	0.94	2.54	120	79.5	91.4	73.9	71.8	83.2
Measured + Indicated	205	1.01	163.0	0.29	0.95	2.59	120	79.5	91.4	73.9	71.8	83.2
Inferred Mineral Resources	1,838	1.03	100.3	0.23	1.29	3.62	120	79.5	91.4	73.9	71.8	83.2
Alta Gracia							AuEq (g/t)
Measured Mineral Resources	27	0.81	370.6	–	–	–	2.35	85.0	72.0	–	–	–
Indicated Mineral Resources	141	0.49	270.0	–	–	–	2.35	85.0	72.0	–	–	–
Measured + Indicated	168	0.54	286.1	–	–	–	2.35	85.0	72.0	–	–	–
Inferred Mineral Resources	148	0.62	295.6	–	–	–	2.35	85.0	72.0	–	–	–

Notes on Mineral Resources:

1. Mineral Resources estimated at December 31, 2024 are based on $2,200/oz for gold, $28.00/oz for silver, $4.52/pound for copper, $1.00/pound for lead and $1.22/pound for zinc. The metal prices used are based on conservative estimates of the average median consensus prices for each of the three years starting in 2025 through 2027 as provided by Bloomberg’s consensus commodity price forecast as at January 7, 2025. The 2027 consensus was used for the remaining life of mine.

2. The definitions for Mineral Resources in S-K 1300 were followed, which are consistent with definitions outlined by the CIM (2014) and are exclusive of Mineral Reserves.

3. The Arista Mine cut-off grade applied to Mineral Resources estimated at December 31, 2024 is $120/tonne NSR.

4. No appreciable amounts of base metals are present in the Alta Gracia veins identified to date. A breakeven cut-off grade of 2.35 g/t AuEq was used for Mineral Resources using gold and silver only to calculate gold equivalencies.

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

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

Gold Resource Corporation

31

During 2025, the Company completed an updated evaluation of its geological interpretations, block models, metallurgical recoveries, and economic assumptions supporting the Mineral Resource estimate at DDGM to enhance the reliability of mine planning and forecasting. Mining methods, ground control, and other parameters were also reviewed. As a result of this review, measured and indicated Mineral Resources decreased from approximately 0.37 million tonnes at December 31, 2024 to approximately 0.23 million tonnes at December 31, 2025. The primary factor for this decrease was the increase in the NSR cutoff grade from $120/tonne to $150/tonne, reflecting updated cost and economic assumptions. In addition, 2025 plant metallurgical recoveries were incorporated in the NSR calculations and more restrictive resource modelling parameters were applied. The total inferred Mineral Resources decreased from approximately 1.99 million tonnes at December 31, 2024 to approximately 1.51 million tonnes at December 31, 2025. The decrease in inferred Mineral Resources primarily reflects the updated geologic interpretation, the higher NSR cut-off grade, and the absence of step-out or expansion drilling during 2025.

More information regarding the assumptions, methodologies, and procedures utilized in the estimation of Mineral Resources at DDGM can be found in the updated Don David Gold Mine Technical Report Summary, effective as of December 31, 2025, which is incorporated by reference as Exhibit 96.2 to this Form 10-K (the “DDGM Technical Report Summary”).

Back Forty Project – Summary of Gold, Silver, and Base Metal Mineral Resources at December 31, 2024 and 2025(1) (2) (3) (4)

Description Tonnes
(k/t)

Gold (g/t)

Silver (g/t)

Copper (%)

Lead (%)

Zinc (%)

Cut-off grade

Back Forty – Open Pit							$/Tonne
Measured Mineral Resources	–	–	–	–		– –	–
Indicated Mineral Resources	9,360	2.41	28.1	0.36		– 3.74	33
Measured + Indicated	9,360	2.41	28.1	0.36		– 3.74	33
Inferred Mineral Resources	566	2.70	48.8	0.35		– 1.31	33
Back Forty – Underground							AuEq (g/t)
Measured Mineral Resources	–	–	–	–		– –	–
Indicated Mineral Resources	5,137	1.86	24.1	0.41		– 2.65	73
Measured + Indicated	5,137	1.86	24.1	0.41		– 2.65	73
Inferred Mineral Resources	627	2.00	26.1	0.37		– 2.89	73

Notes on Mineral Resources:

1. Mineral Resources estimated at December 31, 2024 and 2025 are based on metal price assumptions of $1,800/oz for gold, $23.30/oz for silver,

   $3.90/pound for copper, $0.95/pound for lead and $1.25/pound for zinc. These prices are derived from the average median consensus price forecasts for the period 2024 through 2028, as provided by the Bank of Montreal in June 2023, and have not been updated to reflect economic changes. The median price was based on the price estimates contributed by 38 participating financial institutions. These prices are also very similar to the three-year average.

2. The definitions for Mineral Resources in S-K 1300 were followed, which are consistent with definitions outlined by CIM (2014) and are exclusive of Mineral Reserves.

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

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

Following the completion of the optimization work for the Back Forty Project, the Company published an update on indicated and inferred Mineral Resources in the Back Forty Project Technical Report Summary released in October 2023. A measured Mineral Resource estimate or a Mineral Reserve estimate have yet to be established for the Back Forty Project.

Gold Resource Corporation

32

More information regarding the assumptions, methodologies, and procedures utilized in the estimation of Mineral Resources at Back Forty can be found in the Back Forty Project Technical Report Summary, which is incorporated by reference as Exhibit 96.1 to this Form 10-K.

Mineral Reserves

Under Regulation S-K 1300, a “Mineral Reserve” is defined as “an estimate of tonnage and grade or quality of measured and indicated Mineral Resources that, in the opinion of the qualified person, can be the basis of an economically viable project.”

The following tables summarize the estimated Mineral Reserves at DDGM:

Don David Gold Mine – Summary of Gold, Silver and Base Metal Mineral Reserves at December 31, 2025 (1) (2) (3) (4)

Tonnes	Gold	Silver	Cu	Pb	Zn	Cut-off	Au	Ag	Cu	Pb	Zn
(kt)	(g/t)	(g/t)	(%)	(%)	(%)	Grade (2)	(%)	(%)	(%)	(%)	(%)

Recovery (%)

Description

Don David Gold Mine
Arista Mine (2)							$/Tonne
Proven Mineral Reserves	26	1.91	475.7	0.22	0.81	1.90	150	71.3	85.0	58.9	65.8	76.3
Probable Mineral Reserves	626	1.16	183.9	0.18	0.82	2.52	150	71.3	85.0	58.9	65.8	76.3
Arista Mine Total	652	1.19	195.7	0.18	0.82	2.49
Alta Gracia Mine (3)							AuEq
							(g/t)
Proven Mineral Reserves	–		–	–	–	–	– –	–	–
Probable Mineral Reserves	–		–	–	–	–	– –	–	–
Alta Gracia Mine Total	–		–	–
Don David Gold Mine Total	652		1.19	195.7
Notes on Mineral Reserves:

1. Mineral Reserves estimated at December 31, 2025 are based on metal price assumptions of $3,000/oz for gold, $38.00/oz for silver, $4.54/pound for copper, $0.95/pound for lead and $1.25/pound for zinc. The metal prices used are based on conservative estimates of the average median consensus prices for each of the three years starting in 2026 through 2028 as provided by Bloomberg’s consensus commodity price forecast as at November 21, 2025. The 2028 consensus was used for the remaining life of mine.

2. The Arista Mine NSR cut-off grades for Mineral Reserves are $150/tonne.

3. Alta Gracia Mineral Reserves reported as of December 31, 2022 were reclassified as Mineral Resources as of December 31, 2023 and remain classified as Mineral Resources as of December 31, 2025.

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

Gold Resource Corporation

33

For comparison, as at December 31, 2024, DDGM’s estimates of Mineral Reserves are presented in the table below.

Don David Gold Mine – Summary of Gold, Silver and Base Metal Mineral Reserves at December 31, 2024 (1) (2) (3) (4)

Tonnes	Gold	Silver	Cu	Pb	Zn	Cut-off	Au	Ag	Cu	Pb	Zn
(kt)	(g/t)	(g/t)	(%)	(%)	(%)	Grade (2)	(%)	(%)	(%)	(%)	(%)

Recovery (%)

Description

Don David Gold Mine
Arista Mine (2)							$/Tonne
Proven Mineral Reserves	60	2.25	276.2	0.24	1.20	3.14	120	79.5	91.4	73.9	71.8	83.2
Probable Mineral Reserves	1,057	1.21	135.6	0.17	0.70	2.19	120	79.5	91.4	73.9	71.8	83.2
Arista Mine Total	1,117	1.26	143.1	0.18	0.73	2.24
Alta Gracia Mine (3)							AuEq
							(g/t)
Proven Mineral Reserves	–		–	–	–	–	– –	–	–
Probable Mineral Reserves	–		–	–	–	–	– –	–	–
Alta Gracia Mine Total	–
Don David Gold Mine Total	1,117		1.26	143.1
Notes on Mineral Reserves:

1. Mineral Resources estimated at December 31, 2024 are based on $2,200/oz for gold, $28.00/oz for silver, $4.52/pound for copper, $1.00/pound for lead and $1.22/pound for zinc. The metal prices used are based on conservative estimates of the average median consensus prices for each of the three years starting in 2025 through 2027 as provided by Bloomberg’s consensus commodity price forecast as at January 7, 2025. The 2027 consensus was used for the remaining life of mine.

2. The Arista Mine NSR cut-off grades for Mineral Reserves are $120/tonne.

3. Alta Gracia Mineral Reserves reported at December 31, 2022 have been downgraded to Mineral Resources as of December 31, 2023 and remained classified as Mineral Resources as of December 31, 2024.

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

Proven and probable Mineral Reserves decreased from 1.12 million tonnes at December 31, 2024 to 0.65 million tonnes at December 31, 2025. This decrease was primarily due to depletion of 0.27 million tonnes from 2025 mining activities and an additional reduction of 0.49 million tonnes resulting from engineering deductions, including an increase in the cut-off grade from $120/t to $150/t NSR, removal of orphaned ore blocks, and tightening of the geologic model at the Arista mine. These reductions were partially offset by the reclassification of 0.30 million tonnes of Mineral Resources to Proven and Probable Mineral Reserves, driven by the results from the 2025 infill and grade-control drilling program at the Three Sisters and Arista vein systems and detailed engineering.

More information regarding the assumptions, methodologies, and procedures utilized in the estimation of Mineral Reserves can be found in the DDGM Technical Report Summary incorporated by reference as Exhibit 96.2 to this Form 10-K.

Gold Resource Corporation

34

Don David Gold Mine

The Company’s portfolio of properties comprising DDGM is located along a 55-kilometer, north-west trending stretch of the San Jose structural corridor within the Sierra Madre del Sur mountain range in the state of Oaxaca, Mexico. The property package covers approximately 551 square kilometers of contiguous mineral concessions and encompasses three historic mining centers. Within this land package, the Company continues to conduct strategic planning and prioritization of regional surface exploration activities across multiple properties, including Alta Gracia, Margaritas, Chamizo, Rey, Jabali and Fuego. The map below shows the general location of the DDGM property areas.

The Company was granted concessions from the Mexican federal government to explore and mine the properties in Mexico. Please see below Item 2. Properties-Mining Concessions and Regulations in Mexico for additional information. The Company holds certain properties as the concession holder and lease other properties from third parties. The Company is required to pay concession fees to the Mexican government to maintain its interest in these concessions, and it pays concession fees for all the mineral properties, including those which are subject to the third-party lease.

Gold Resource Corporation

35

The table below details information related to the mining concessions that comprise the properties in Oaxaca, Mexico:

						2025
	Total Number of				Acquisition Date	Maintenance
	Concessions		Total Size		Range	Fees Paid
			(in hectares)			(in thousands)
Production Stage Properties:
Arista	18		24,372		2002 to 2016	$ 565
Alta Gracia	3		5,175		2008	119
Total Production Stage Properties:			29,547			$ 684
Exploration Stage Properties:
Rey	4	2,335		2002 to 2009		$ 54
Chamizo	2	19,758		2011 to 2013		462
Margaritas	1	925		2002		21
Fuego	1	2,554		2013		60
Total Exploration Stage Properties:		25,572				$ 597
Total:	29	55,119		$			1,281

Production Stage Properties

Arista & Alta Gracia Mines

History: The Arista and Alta Gracia Mines are located within the regional Tlacolula mining district in the state of Oaxaca, in southern Mexico. According to the Mexican Geological Survey, the Servicio Geologico Mexicano (“SGM”), mining activity in the Tlacolula district began in the early 1880s and resulted in the production of approximately 300,000 ounces of gold and silver from an ore shoot in the La Leona mine. However, no separate production amounts were reported for each metal. According to the SGM, in 1892, two smelters were built and operated (Magdalena Teitipac and O’Kelly) near the village of Tlacolula to process 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 particular interest in the Margaritas mine. Many of these historical mines are located within mining concessions currently controlled by the Company.

Although the DDGM Arista Mine and Alta Gracia Mine are situated within the smaller mining subdistricts of San Jose de Gracia and Alta Gracia, respectively, only small-scale artisanal mining was historically conducted in these areas. No reliable production records exist for the historic production from within the Arista and Alta Gracia Project areas.

Arista Mine

Background: The Arista Mine consists of 18 mining concessions totaling 24,372 hectares.

In 2002, the Company entered into lease agreements for three initial concessions from a third-party. Two of these concessions form part of the Arista Mine, while the third concession comprises the Margaritas property. In November 2023, the royalty terms associated with the lease agreement were renegotiated, reducing the net smelter return (“NSR”) royalty from 4% to 3% for production sold in the form of gold/silver doré, and from 5% to 3% for production sold in concentrate form. Subject to meeting minimum exploration requirements, there is no expiration term for the lease. The Company may terminate the lease at any time upon written notice to the lessor, and the lessor may terminate the lease if the subsidiary fails to fulfill any of its obligations, which primarily consist of paying the appropriate royalty to the lessor.

Gold Resource Corporation

36

Initial drilling and exploration activities commenced at the Arista Mine in August 2003. As of December 31, 2025, the Company has completed 1,992 diamond drill holes (including both surface and underground programs) totaling 509,570 meters. In addition, 166 reverse circulation drill holes have been completed for a total of 14,367 meters. Cumulatively, the Company has drilled 2,158 holes totaling 523,937 meters across the Arista Mine, Alta Gracia, Rey, and Margaritas properties.

DDGM Ore Terminal

In 2010, the Company acquired additional concessions from a third-party at no additional cost, which are subject to a 2% royalty. The Company also filed for and received additional concessions from the Mexican government that are not part of the concessions leased or acquired from the third-party. Of these, two concessions are considered part of the Arista Mine.

Location and Access: The Arista Mine is located in the Sierra Madre del Sur Mountains of southern Mexico, in the central part of the state of Oaxaca. The property lies along a major paved highway approximately 120 kilometers southeast of Oaxaca City, the state capital, and approximately four kilometers northwest of the village of San Jose de Gracia. The Company has constructed gravel and paved access roads from the village to the mine and processing facility, providing adequate access to the property.

The climate in the Arista Mine area is dry and warm to very warm, with most rainfall occurring between June and September and average annual precipitation of 432 millimeters. The average annual temperature is 26.6 degrees Celsius. The terrain is rocky and characterized by arid vegetation. Subsistence farming is practiced locally, with agave cactus cultivated as the primary agricultural crop for the production of mezcal.

Gold Resource Corporation

37

Geology and Mineralization: The Arista Mine is located within the San Jose de Gracia mining district in the state of Oaxaca, Mexico. District-scale geology is dominated by multiple volcanic domes of varying scales, including likely non-vented intrusive domes, which overlie a pre-volcanic sedimentary rock basement. Gold and silver mineralization within the district is related to the manifestations of this classic volcanogenic system and is classified as epithermal in character.

Historically, the Company produced ore from two locations at the Arista Mine: an open pit operation and an underground mine. Mineralization mined from the open pit is interpreted as low-sulfidation epithermal in style, consisting predominantly of gold with some silver and no significant base metal content. In 2011, mining activities were completed in the open pit, and the pit is currently being backfilled and reclaimed using filtered dry-stack tailings deposition. Mineralization at the Arista underground mine is interpreted as intermediate-sulphidation epithermal in style and contains gold, silver, copper, lead, and zinc. The principal host rock for the three vein systems (Arista, Switchback and Three Sisters) that comprise the Arista mine is primarily andesite.

Facilities: The processing facility and other infrastructure at the Arista Mine was constructed for approximately

$35.0 million in 2009, and the processing facility was expanded in 2012 and 2013 for an additional $23.0 million. The flotation mill expansion, completed at the end of 2013, increased the number of flotation cells, added a second ball mill to allow for additional processing capacity, and added a Knelson gravity concentrator. In 2014, a doré processing facility was completed. In 2019, an increase in pumping capacity to the cyclones in the plant resulted in plant capacity increasing to nominal 2,000 tonnes per day. The DDGM processing facility is flexible in its ability to process several types of mineralization. It has a differential flotation section capable of processing polymetallic ore and producing up to three separate concentrate products. The facility also has an agitated leach circuit capable of producing gold and silver doré.

Gold Resource Corporation

38

The Company obtained water rights from the Mexican government for an amount of water that it believes is sufficient to meet its operating requirements and pump it approximately five kilometers to the site from a permitted well located near the Totolapam River.

Additional improvements at the site include electrical power lines connecting to the Mexican national power grid, installation of backup diesel generation power plants and switch gear, paving a three-kilometer section of the road from the mine to the processing facility, construction of a surface maintenance garage and fuel station, construction of haul roads from the mine site to the processing facility, office space at the processing facility, an assay lab, an exploration office, tailings impoundment facilities and lift, a paste fill plant, mine camp facilities, the filtration plant, the dry stack facility, and other infrastructure.

Exploration Activities: In 2025, the Company successfully completed an underground diamond drilling program at the Arista Mine, consisting of 105 diamond drill holes totaling 13,418 meters. The program included 78 underground grade-control drill holes totaling 8,557 meters, which were focused on upgrading Mineral Resources to Mineral Reserves within multiple veins of the Arista, Three Sisters and Switchback vein systems. In addition, 27 underground infill drill holes totaling 4,861 meters were completed to upgrade previously defined Inferred Mineral Resources to Measured and Indicated Mineral Resource categories. This drilling further delineated and refined multiple sub-parallel veins within the Three Sisters and Arista vein systems and upgraded several high-grade zones up- and down-dip and along strike from existing workings, within and adjacent to existing Mineral Resources.

Underground expansion drilling activities at the Arista Mine remained suspended during 2025 in order to prioritize drilling in support of near-term production, primarily within the Arista and Three Sisters vein systems. During the year, the Company completed more than 485 meters of underground drift development at the Arista Mine to support infill and grade-control drilling and to prepare for planned expansion drilling in 2026. Expansion drilling is expected to focus on the Three Sisters vein system, including the Gloria vein, along strike to the northwest and down-dip, as well as on the northern and down-dip extensions of the Marena North and Splay 31 veins within the Arista vein system.

The Arista and Switchback vein systems each extend for more than 1.5 kilometers along strike and remain open along strike, and both up- and down-dip. The Three Sisters vein system, which currently comprises 24 veins and vein segments, including the Gloria vein, is located at the northern extent of the Arista Mine underground workings, between the Switchback and Arista systems. The Three Sisters system has a defined strike length of more than 750 meters and remains open along strike and both up- and down-dip. Infill and expansion drilling planned for 2026 will continue to prioritize resource expansion within the Three Sisters system, as well as the northern extensions of veins within the Arista system.

Surface exploration activities during 2025 in the Arista project area focused on the evaluation and prioritization of advanced-stage exploration targets within the approximately 551 square kilometer land package controlled by DDGM surrounding the Arista Mine. These activities included the re-processing and integration of historical geologic information, including mapping, sampling, geophysical surveys, and drill data, from several projects, including Rey, Margaritas, Chamizo, Jabali and Alta Gracia. Prospective areas proximal to the Arista Mine are in the process of being re-evaluated for near-term exploration potential, with the objective of defining additional near-mine drill targets.

Please see Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations for additional information concerning mining operations at the Alta Gracia project.

Alta Gracia Mine

Background: In 2008, the Company was granted mineral claims adjacent to the Margaritas property in the Alta Gracia mining district through the filing of three mining concessions known as David Fracción I, David Fracción II, and La Herradura, totaling 5,175 hectares.

Gold Resource Corporation

39

Attachments

• Original document
• Permalink

Disclaimer

Gold Resource Corporation published this content on March 18, 2026, and is solely responsible for the information contained herein. Distributed via Public Technologies (PUBT), unedited and unaltered, on March 18, 2026 at 22:01 UTC.