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Golden Minerals Announces Updated Preliminary Economic Assessment FOR Velardeña Project

Economic Studies

GOLDEN MINERALS ANNOUNCES UPDATED PRELIMINARY ECONOMIC

ASSESSMENT FOR VELARDEÑA PROJECT

GOLDEN, Colo., April 02, 2020 -- Golden Minerals Company (NYSE American and TSX: AUMN) (“Golden Minerals”, “Golden”

or “the Company”) is pleased to announce positive results from the updated Mineral Resource Estimate and Preliminary

Economic Assessment (“PEA”) for its Velardeña Properties, a 100%-owned silver and gold project located in Durango State,

Mexico.

PEA Financial and Economic Highlights

Tetra Tech, an independent engineering company, has prepared the PEA for the Company in accordance with Canadian

National Instrument 43-101 “Standards of Disclosure of Mineral Projects” (“NI 43-101”). The PEA assumes prices of $1,324/oz

gold, $16.23/oz silver, $0.90/lb lead and $1.25/lb zinc. Preliminary results of the economic analysis are shown in pre-tax U.S.

Dollars as highlighted below. The complete PEA will be published on SEDAR within 45 days of this press release.

• Pre-tax net present value (“NPV”): (US)$85.9 million at an 8% discount rate

• Pre-tax Internal rate of return (“IRR”):  138.6%

• Pre-tax Payback period:  1 year

• Total pre-production capital cost:  $10.27 million, including 10% contingency*

• Post-production and sustaining capital:  $ 15.93 million, including 10% contingency

• Pre-production development time:  1 year

• Life of mine (“LOM”):  10 years

• LOM contained silver:  12.3 Moz; LOM contained gold:  188 Koz

• LOM average silver grade:  337 grams per tonne (“g/t”); LOM average gold grade:  5.15 g/t

• LOM pre-tax free cash flow:  $130.2 million

• LOM payable silver:  10.2 Moz; LOM payable gold production:  119 Koz

• LOM payable Ageq:  19.7 Moz (Au and Ag only at a ratio of 80Ag:1Au)

*Capital estimate for bio-oxidation plant includes additional contingency

Golden Minerals President and Chief Executive Officer Warren M. Rehn remarked, “The Velardeña mines now present an

attractive scenario for a potential restart. The most difficult challenge we previously faced at the Velardeña mines was the low

payable gold recovery, a challenge which we believe is solved with the addition of a relatively low-cost bio-oxidation circuit at

our existing processing facility. Because we already have most of what is required for recommencing mining and processing,

the capital needs for the project are modest. The one-year payback on pre-production capital signifies a very robust project.

The projected cash costs for silver production at less than a dollar per ounce net of byproducts points to the strong projected

profitability of this operation.”

Pre-Tax Technical Economic Model Results  

Item Total per Tonne  

($000s) of Material  

Gross Payable $375,728  $330.19  

TCs, RCs and penalties ($33,130)  ($29.12)  

Freight & Insurance (1) ($12,311)  ($10.82)  

NSR $330,288  $290.21  

Operating Costs     

Mining costs ($94,303)  ($82.87)  

Milling costs ($54,241)  ($47.67)  

Site Administration ($15,656)  ($13.76)  

G&A ($8,014)  ($7.04)  

Federal Mining Royalty ($1,651)  ($1.45)  

  ($173,866)   ($152.79)  

Operating Margin $156,423  $137.46  

Capital Costs     

Mine Development ($10,791)  ($9.48)  

Process Plant ($9,460)  ($8.31)  

Infrastructure ($782)  ($0.69)  

Other Non-Operating Costs* ($5,158)  ($4.53)  

Cash Flow $130,232  $114.44  

NPV8% $85,914    

IRR 139%    

Payback (years) 1    

* includes contingency equal to 10% of capital costs above  

Cash Costs   

Cash cost per payable Ag ounce, net of by products $0.92  

All in Sustainable cost per payable Ag ounce, net of by products $3.48  

The updated PEA has been prepared to incorporate new and updated elements of the project database and mine plan, most

notably the inclusion of bio-oxidation treatment of gold concentrates. In late 2019, Golden obtained successful results from

testing Velardeña gold concentrate material using Finnish firm Outotec’s “BIOX” process. BIOX is a unique and sustainable

technology that was developed to pre-treat refractory ores and concentrates ahead of conventional cyanide leaching. The gold

in these types of mineralized material, such as those found at Velardeña, is encapsulated in pyrite and arsenopyrite which

prevents the gold from being successfully cyanide leached. BIOX utilizes bacteria to oxidize these sulfide materials, thereby

exposing the gold for subsequent cyanide leaching and increasing overall gold recoveries. Golden Minerals believes this

technology is key to unlocking successful and sustainable value from production at Velardeña. Indeed, 2019 BIOX testing of

Velardeña material achieved gold recoveries of 92%, compared to sub-30% gold recoveries realized when Golden last operated

Velardeña in 2015.

In the coming months, the Company plans to continue to optimize the mine plan and processing details in preparation for

future test-mining and processing in advance of establishing a definite schedule for restarting commercial production at the

Velardeña mines and the installation of the bio-oxidation circuit.

Mine Planning

Given changes to the resource models and project parameters, a new preliminary mine plan was developed. Mine staff

performed test mining to prove a selective mining minimum width of 0.7 meters. Based on the new resource models, new

dilution calculations and the updated NSR, the mining areas have changed from the previous PEA. The 2015 PEA considered

only a limited subset of areas and tonnes, whereas the update considers all principal veins for the mine plan. This updated

mine plan includes 1.14 M tonnes of sulfide material, with a mine life of approximately 10 years at a rate of 310 tonnes per

day.

The table below shows the potentially minable material within the preliminary mine plan. 

Mine Plan

Category Total/Avg

Tonnes 1,137,949

NSR ($/T) 290

Ag (gpt) 337

Contained Ag oz 12,325,300

Au (gpt) 5.15

Contained Au (oz) 188,250

Pb (%) 1.32

Contained Pb (lbs) 33,096,126

Zn (%) 1.63

Contained Zn(lbs) 40,886,729

Sensitivity Tables

Project sensitivity to metals prices, capital and operating costs are shown below. The project is most sensitive to metals

prices, and to silver slightly more than gold. Given the low remaining required capital expenditures, the project is least

sensitive to capital.

A graph accompanying this announcement is available at

https://www.globenewswire.com/NewsRoom/AttachmentNg/676813d4-fb5b-429c-8c60-bccc6291ed7b

Updated Mineral Resource Estimate

The updated Mineral Resource Estimate incorporates work completed on the project database since the previous Technical

Report (February 20, 2015:  Tetra Tech, NI 43-101 Technical Report and Preliminary Economic Assessment, Velardeña

Project, Durango State, Mexico). The database was evaluated and intervals were re-coded by vein, which led to an update of

the principal veins (CC, C1, A4, F1, G1, San Mateo, Roca Negra, Hiletas, Terneras, Chicago and Escondida), including

wireframe models. The new wireframe models were created in Leapfrog software for the principal veins. Resource estimations

for these veins were completed using a 3D block model with a block factor.

Estimation of secondary veins was conducted in the same manner as the 2015 resource estimate, using point models based

on vein surfaces, but with updated parameters including minimum 0.7 meters dilution, updated mined out shapes, updated

property boundaries and the new NSR cutoff value of $125 per tonne of ore.

The updated Resource Estimate is shown below: 

Classification Mineral

Type

NSR

Cutoff Tonnes

Grade

Ag

g/t

Grade

Au

g/t

Grade

Pb%

Grade

Zn% Ag toz Au toz Pb lb Zn lb

Measured Oxide 125 135,000 260 5.55 1.72 1.54 1,130,000 24,000 5,120,000 4,570,000

Indicated Oxide 125 301,000 250 4.89 1.7 1.47 2,420,000 47,000 11,300,000 9,750,000

Measured +

Indicated Oxide 125 436,000 253 5.1 1.71 1.49 3,550,000 71,000 16,430,000 14,310,000

Inferred Oxide 125 372,000 399 4.82 2.52 1.46 4,770,000 58,000 20,680,000 11,950,000

Measured Sulfide 125 269,000 346 5.38 1.53 1.88 3,000,000 47,000 9,100,000 11,140,000

Indicated Sulfide 125 645,000 327 4.62 1.43 1.94 6,790,000 96,000 20,300,000 27,530,000

Measured +

Indicated Sulfide 125 915,000 333 4.84 1.46 1.92 9,790,000 142,000 29,410,000 38,670,000

Inferred Sulfide 125 1,393,000 342 4.7 1.51 1.97 15,320,000 211,000 46,380,000 60,400,000

Measured All 125 404,000 317 5.43 1.6 1.76 4,120,000 71,000 14,220,000 15,710,000

Indicated All 125 946,000 303 4.71 1.52 1.79 9,220,000 143,000 31,610,000 37,280,000

Measured +

Indicated All 125 1,351,000 307 4.92 1.54 1.78 13,340,000 214,000 45,830,000 52,990,000

Inferred All 125 1,765,000 354 4.73 1.72 1.86 20,080,000 268,000 67,060,000 72,350,000

Notes to accompany Mineral Resource table (effective date December 31, 2019):

1) Resources are reported as diluted Tonnes and grade to 0.7-meter fixed width

2) Metal prices for NSR cutoff are 3-year trailing average as of December 2019: (US) $16.30/troy oz Ag, $1,305/troy oz Au,

$0.99/lb Pb and $1.27/lb Zn

3) The cutoff value was calculated based on mining and milling costs from the 2015 operation and estimated payable

recoveries including smelting and refining fees

4) Columns may not total due to rounding

5) Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability

PEA Information and Cautionary Note Regarding Inferred Resources

The discounted cash flows in the PEA are provided pre-tax and are prepared in compliance with NI 43-101 of the Canadian

Securities Administrators. The following Qualified Persons from Tetra Tech will co-author the technical report that will be filed

on SEDAR within 45 days of this news release:  Dr. Guillermo Dante Ramírez Rodríguez, Mr. Leonel López, Mr. Randolph P.

Schneider, and Ms. Kira Lyn Johnson.  Each of these Qualified Persons has reviewed and approved the information presented

in this news release that was derived from the sections of the PEA study for which they were responsible. Each of the named

Qualified Persons is independent of Golden Minerals.

The mine plan evaluated in the PEA is preliminary in nature and additional technical studies will need to be completed in order

to fully assess its viability. There is no certainty that a production decision will be made to reactivate the Velardeña mine or

that the economic results described in the PEA will be realized. In addition, we may determine to proceed with a production

decision without completion of customary feasibility studies demonstrating the economic viability of reactivation of Velardeña.

A mine production decision that is made without a feasibility study carries additional potential risks which include, but are not

limited to, (i) increased uncertainty as to projected initial and sustaining capital costs and operating costs, rates of production

and average grades, and (ii) the inclusion of Inferred Mineral Resources, as defined by NI 43-101 that are considered too

speculative geologically to have the economic considerations applied to them that would enable them to be converted to a

Mineral Reserve, as defined by NI 43-101. Mine design and mining schedules, metallurgical flow sheets and process plant

designs may require additional detailed work and economic analysis and internal studies to ensure satisfactory operational

conditions and decisions regarding future targeted production. In addition, the results of test mining may impact projected

capital and operating costs, with the result that the projected NPV, IRR and cash flows may be adversely impacted.

No mineral reserves have been estimated for the project.  Mineral resources that are not mineral reserves do not have

demonstrated economic viability.

Cautionary Note to United States Investors Regarding Estimates of Indicated and Inferred Mineral Resources

This press release uses the terms "mineral resources", "indicated mineral resources" and "inferred mineral resources" which

are defined in and required to be disclosed by NI 43-101. We advise U.S. investors that these terms are not recognized under

the SEC Industry Guide 7. Accordingly, the disclosures regarding mineralization in this news release may not be comparable

to similar information disclosed by Golden Minerals in the reports it files with the SEC. The estimation of measured resources

and indicated resources involves greater uncertainty as to their existence and economic feasibility than the estimation of

proven and probable reserves. The estimation of inferred resources involves far greater uncertainty as to their existence and

economic viability than the estimation of other categories of resources. US investors are cautioned not to assume that any or

all of Mineral Resources are economically or legally mineable or that these Mineral Resources will ever be converted into

Mineral Reserves. In addition, the SEC normally only permits issuers to report mineralization that does not constitute SEC

Industry Guide 7 compliant “reserves” as in-place tonnage and grade without reference to unit amounts. U.S. investors are

urged to consider closely the disclosure in our Form 10-K and other SEC filings.

Review by Qualified Person and Quality Control

On behalf of Tetra Tech, the technical contents of this press release have been reviewed by the Qualified Persons for the

purposes of NI 43 ‐101. Tetra Tech’s QPs have extensive experience in mineral exploration, mining engineering and

metallurgical processes, and are QP members of the Mining and Metallurgical Society of America and the SME RM.

Non-GAAP Financial Measures

Cash costs per payable silver ounce, net of by-product credits, and all-in sustainable costs per payable silver ounce, net of by-

product credits, are non-GAAP financial measures calculated by the Company as set forth below and may not be comparable

to similar measures reported by other companies.

Cash costs per payable silver ounce, net of by-product credits, include all direct and indirect costs associated with the

physical activities that would generate concentrate and doré products for sale to customers, including mining to gain access

to mineralized materials, mining of mineralized materials and waste, milling, third-party related treatment, refining and

transportation costs, on-site administrative costs and royalties. Cash costs do not include depreciation, depletion,

amortization, exploration expenditures, reclamation and remediation costs, sustaining capital, financing costs, income taxes,

or corporate general and administrative costs not directly or indirectly related to the Velardeña Properties. By-product credits

include revenues from gold, lead and zinc contained in the products sold to customers during the period. Cash costs, after by-

product credits, are divided by the number of payable silver ounces generated by the plant for the period to arrive at cash

costs, after by-product credits, per payable ounce of silver. All-in sustainable costs per payable silver ounce, net of by-product

credits, begins with cash costs per payable silver ounce, net of by-product credits, and also includes pre and post-production

capital and sustaining capital.

Cost of sales is the most comparable financial measure, calculated in accordance with GAAP, to cash costs. As compared to

cash costs, cost of sales includes adjustments for changes in inventory and excludes net revenue from by-products and third-

party related treatment, refining and transportation costs, which are reported as part of revenue in accordance with GAAP.

About Golden Minerals

Golden Minerals is a Delaware corporation based in Golden, Colorado. The Company is primarily focused on advancing its

Velardeña Properties in Mexico and its El Quevar silver property in Argentina, as well as acquiring and advancing mining

properties in Mexico and Nevada.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as

amended and Section 21E of the Securities Exchange Act of 1934, as amended, and applicable Canadian securities

legislation, including statements the Velardeña PEA results (including cost estimates, assumption of commodity prices,

development timing, expected cash flows and life of mine and production expectations); future activities at Velardeña, and the

possibility of future development; and estimates of mineral resources for the Velardeña project. These statements are subject

to risks and uncertainties, including:  the reasonability of the economic assumptions at the basis of the results of the

Velardeña PEA and technical report; changes in interpretations of geological, geostatistical, metallurgical, mining or

processing information and interpretations of the information resulting from future exploration, analysis or mining and

processing experience; declines in general economic conditions; fluctuations in exchange rates and changes in political

conditions, in tax, royalty, environmental and other laws in Mexico; new information from drilling programs or other exploration

or analysis; unexpected variations in mineral grades, types and metallurgy; fluctuations in commodity prices; and failure of

mined material or veins mined to meet expectations. Additional risks relating to Golden Minerals may be found in the periodic

and current reports filed with the Securities and Exchange Commission by Golden Minerals, including the Company’s Annual

Report on Form 10-K for the year ended December 31, 2019.

For additional information please visit http://www.goldenminerals.com/ or contact:

Golden Minerals Company

Karen Winkler, Director of Investor Relations

(303) 839‐5060

SOURCE: Golden Minerals Company