Golden Minerals Co

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

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

For the fiscal year ended December 31,2025

or

☐ 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 1-13627

(Exact Name of Registrant as Specified in its Charter)

(303) 839-5060

(Registrant’s telephone number, including area code)

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

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

Common Stock, $0.01 par value

(Title of Class)

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, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer ☐ 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 checkmark 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 the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes☐ No☒

The aggregate market value of the voting and non-voting common equity held by non-affiliates as of June 30, 2025 was approximately $2.71 million, based on the closing price of the registrant’s common stock of $0.18 per share on the OTC on June 30, 2025. For the purpose of this calculation, the registrant has assumed that its affiliates as of June 30, 2025 included all directors and officers and one shareholder that held approximately 10% of its outstanding common stock. The number of shares of common stock outstanding on March 31, 2026 was 15,053,048.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the registrant’s Definitive Proxy Statement to be filed with the Securities and Exchange Commission pursuant to Regulation 14A in connection with the 2026 Annual Meeting of Stockholders are incorporated by reference in Part III of this Annual Report on Form 10-K.

FORM 10-K

YEAR ENDED DECEMBER 31, 2025

INDEX

Unless otherwise specified, all dollar amounts are expressed in United States dollars and all references to “dollars” or “$” are to United States dollars.

References herein to the “Company,” “we,” “us” or “Golden Minerals” refer to Golden Minerals Company and, unless context requires otherwise, its subsidiaries.

FORWARD-LOOKING STATEMENTS

Some information contained in or incorporated by reference into this Annual Report on Form 10-K (this “Form 10-K”) may contain forward-looking statements and forward-looking information (collectively, “forward-looking statements”) within the meaning of the United States Private Securities Litigation Reform Act of 1995 and other applicable securities laws. We use 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. These statements include comments relating to (i) our anticipated near-term capital needs and potential sources of capital; (ii) our plans regarding exploration activities at the Desierto project and the completion of the related joint venture documents and formation of the joint venture with Cascadero Copper Corporation (“Cascadero”); (iii) plans regarding our Sand Canyon exploration property in Nevada; (iv) projected spending during 2026; and (v) statements concerning our financial condition, business strategies, business and legal risks, and our financial outlook for 2026, including anticipated expenditures and cash inflows during the year. Although we believe the expectations and assumptions reflected in those forward-looking statements are reasonable, we cannot assure you that these expectations and assumptions will prove to be correct. Our actual results could differ materially from those expressed or implied in these forward-looking statements as a result of various factors described in this Form 10-K, including:

Many of these factors are beyond our ability to control or predict. Although we believe that the expectations reflected in our 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 our forward-looking statements. These statements speak only as of the date of this Form 10-K. Except as required by law, we are 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 us and persons acting on our behalf are qualified in their entirety by the cautionary statements contained in this section and elsewhere in this Form 10-K.

CONVERSION TABLE

In this Form 10-K, figures are presented in both United States standard and metric measurements. Conversion rates from United States standard measurement systems to metric and metric to United States standard measurement systems are provided in the table below. All currency references in this Form 10-K are to United States dollars, unless otherwise indicated.

GLOSSARY OF SELECTED MINING TERMS

“Base metal” means a classification of non-ferrous metals usually considered to be of low value and higher chemical activity when compared with the precious metals (gold, silver, platinum, etc.). This nonspecific term generally refers to the high-volume, low-value metals copper, lead, tin, and zinc.

“Claim” means a mining interest giving its holder the right to prospect, explore for and exploit minerals within a defined area.

“Concession” means a grant or lease of a tract of land made by a government or other controlling authority in return for stipulated services or a promise that the land will be used for a specific purpose.

“Deposit” means an informal term for an accumulation of minerals.

“Exploration stage” means a property that has no mineral reserves disclosed.

“Feasibility study” means a comprehensive technical and economic study of the selected development option for a mineral project, which includes detailed assessments of all applicable modifying factors, as defined by this section, together with any other relevant operational factors, and detailed financial analysis that are necessary to demonstrate, at the time of reporting, that extraction is economically viable. The results of the study may serve as the basis for a final decision by a proponent or financial institution to proceed with, or finance, the development of the project.

“Grade” means the metal content of mineralized material which for precious metals is usually expressed in troy ounces per ton (2,000 pounds) or in grams per metric tonne, which contains 2,204.6 pounds or 1,000 kilograms.

“Indicated mineral resource” means that part of a mineral resource for which quantity and grade or quality are estimated on the basis of adequate geological evidence and sampling. The level of geological certainty associated with an indicated mineral resource is sufficient to allow a qualified person to apply modifying factors in sufficient detail to support mine planning and evaluation of the economic viability of the deposit. Because an indicated mineral resource has a lower

level of confidence than the level of confidence of a measured mineral resource, an indicated mineral resource may only be converted to a probable mineral reserve.

“Inferred mineral resource” means that part of a mineral resource for which quantity and grade or quality are estimated on the basis of limited geological evidence and sampling. The level of geological uncertainty associated with an inferred mineral resource is too high to apply relevant technical and economic factors likely to influence the prospects of economic extraction in a manner useful for evaluation of economic viability. Because an inferred mineral resource has the lowest level of geological confidence of all mineral resources, which prevents the application of the modifying factors in a manner useful for evaluation of economic viability, an inferred mineral resource may not be considered when assessing the economic viability of a mining project and may not be converted to a mineral reserve.

“Measured mineral resource” means that part of a mineral resource for which quantity and grade or quality are estimated on the basis of conclusive geological evidence and sampling. The level of geological certainty associated with a measured mineral resource is sufficient to allow a qualified person to apply modifying factors in sufficient detail to support detailed mine planning and final evaluation of the economic viability of the deposit. Because a measured mineral resource has a higher level of confidence than the level of confidence of either an indicated mineral resource or an inferred mineral resource, a measured mineral resource may be converted to a proven mineral reserve or to a probable mineral reserve.

“Mineralization” means the concentration of metals within a body of rock.

“Mineral reserve” means an estimate of tonnage and grade or quality of indicated and measured mineral resources that, in the opinion of the qualified person, can be the basis of an economically viable project. More specifically, it is the economically mineable part of a measured or indicated mineral resource, which includes diluting materials and allowances for losses that may occur when the material is mined or extracted.

“Mining” means the process of extraction and beneficiation of mineral reserves or mineral deposits to produce a marketable metal or mineral product. Exploration continues during the mining process and, in many cases, mineral reserves or mineral deposits are expanded during the life of the mine activities as the exploration potential of the deposit is realized.

“Mining claim” means a mining interest giving its holder the right to prospect, explore for and exploit minerals within a defined area.

“National Instrument 43-101” or “NI 43-101” means the standards of disclosure for mineral projects prescribed by the Canadian Securities Administrators.

“Net smelter return royalty” or “NSR royalty” means a defined percentage of the gross revenue from a resource extraction operation, less a proportionate share of transportation, insurance, and processing costs.

“Open pit” means a mine working or excavation open to the surface.

“Ore” means material containing minerals that can be economically extracted.

“Outcrop” means that part of a geologic formation or structure that appears at the surface of the earth.

“Oxide” means mineralized rock in which some of the original minerals have been oxidized (i.e., combined with oxygen).

“Precious metal” means any of several relatively scarce and valuable metals, such as gold and silver.

“Probable mineral reserves” means the economically mineable part of an indicated and, in some cases, a measured mineral resource.

“Proven mineral reserves” means the economically mineable part of a measured mineral resource and can only result from conversion of a measured mineral resource.

“Reclamation” means the process of returning land to another use after mining is completed.

“Recovery” means that portion of the metal contained in the ore that is successfully extracted by processing, expressed as a percentage.

“Rock formation” means a distinct layer of sedimentary or volcanic rock of similar composition.

“S-K 1300” means subpart 1300 of Regulation S-K promulgated by the U.S. Securities and Exchange Commission, which sets forth the rules and regulations for disclosure by registrants engaged in the mining industry.

“Sampling” means selecting a fractional part of a mineral deposit for analysis.

“SEC” means the U.S. Securities and Exchange Commission.

“Sediment” means solid fragmental material that originates from weathering of rocks and is transported or deposited by air, water, or ice, or that accumulates by other natural agents, such as chemical precipitation from solution or secretion by organisms, and that forms in layers on the earth’s surface at ordinary temperatures in a loose, unconsolidated form.

“Sedimentary” means formed by the deposition of Sediment.

“Stockpile” means discordant igneous intrusion having a surface exposure of less than 40 square miles.

“Sulfide” means a compound of sulfur and some other metallic element or elements where sulfur is in the unoxidized form.

“Tertiary” means the first period of the Cenozoic Era (after the Cretaceous of the Mesozoic Era and before the Quaternary) thought to have covered the span of time between 2 to 3 million years ago and 65 million years ago.

“Vein” means a fissure, fault or crack in a rock filled by minerals that have traveled upwards from some deep source.

“Waste” means rock lacking sufficient grade and/or other characteristics of ore.