Creates a District-Scale, Multi-Million Ounce Gold Developer

VANCOUVER, CANADA / ACCESSWIRE / August 7, 2020 / First Mining Gold Corp. ("First Mining" or the "Company") (TSX:FF)(OTCQX:FFMGF)(FRANKFURT:FMG) is pleased to announce that it has closed the previously announced transaction (the "Transaction") with Treasury Metals Inc. ("Treasury Metals" or "TML") (TSX:TML)(OTCQX:TSRMF)(FRANKFURT:TRC) pursuant to which Treasury Metals has acquired all of the issued and outstanding shares of Tamaka Gold Corporation ("Tamaka"), a wholly-owned subsidiary of First Mining that owns the Goldlund Gold Project ("Goldlund") (the "Transaction"). Combining Goldlund with Treasury Metals' adjacent Goliath Gold Project ("Goliath") has created a district-scale, multi-million-ounce gold project positioned for advancement towards construction in a favourable mining jurisdiction.

"We are delighted to become the largest shareholder of Treasury Metals and are excited to see the combined Goldlund-Goliath project move forward" stated Dan Wilton, CEO of First Mining. "This combination has already unlocked meaningful value for First Mining shareholders and leaves the Company with significant exposure to the strong exploration potential at Goldlund. We are also excited that our shareholders will become direct shareholders in Treasury Metals once we distribute a portion of the equity consideration to First Mining shareholders next year. Treasury Metals is now well-funded to advance both projects through an economic study to better understand the merits and synergies of these adjacent properties. Concurrently, through further drilling and work programs, we look forward to seeing Treasury Metals unlock the significant resource growth potential of both assets through exploration of both the existing resource areas and the district-scale land package."

Under the Transaction, as consideration for the acquisition by Treasury Metals of Tamaka, First Mining received: (i) 130 million common shares ("TML Common Shares") of Treasury Metals (the "Share Consideration"); (ii) 35 million common share purchase warrants of Treasury Metals (the "TML Warrants"), with each TML Warrant entitling the holder thereof to purchase one TML Common Share at an exercise price of $0.50 for a period of 36 months from the closing date of the Transaction (the "Warrant Consideration"); (iii) a 1.5% net smelter returns royalty covering all of the Goldlund claims (the "Goldlund Royalty"), with the option for Treasury Metals to buy-back 0.5% of the Goldlund Royalty for $5.0 million; and (iv) a milestone cash payment of $5.0 million, with 50% payable upon receipt of a final and binding mining lease under the Mining Act (Ontario) to extract ore from an open pit mine at Goldlund, and the remaining 50% payable upon the extraction of 300,000 tonnes of ore from a mine at Goldlund.

As previously announced on June 3, 2020, First Mining intends to distribute 70 million TML Common Shares and 35 million TML Warrants directly to First Mining shareholders within 12 months of closing the Transaction. In connection with the Transaction, Treasury Metals and First Mining also entered into an investor rights agreement (the "Investor Rights Agreement") pursuant to which First Mining was entitled to nominate three directors to the board of directors of Treasury Metals (the "Treasury Board"). Additionally: (i) for so long as First Mining holds greater than 10% of the issued and outstanding TML Common Shares, First Mining shall have the right to nominate two nominees for election to the Treasury Board; and (ii) for so long as First Mining holds greater than 5% but less than 10% of the issued and outstanding TML Common Shares, First Mining shall have the right to nominate one nominee for election to the Treasury Board.

First Mining nominated Daniel W. Wilton, Frazer Bourchier and David Whittle to the Treasury Board, and all three of those individuals were conditionally approved as directors of Treasury Metals, pending closing of the Transaction, by the shareholders of Treasury Metals at TML's Annual General and Special Meeting that was held on August 5, 2020 to approve the Transaction. With the Transaction now closed, Daniel W. Wilton, Frazer Bourchier and David Whittle have all been appointed to the Treasury Board as of the date of this news release. In addition, it is expected that a four-member technical committee will be formed at the next meeting of the Treasury Board and First Mining will be entitled to appoint two members of this committee.

Goldlund-Goldlund Work Program

Treasury Metals has initiated a number of important work programs to advance both the Goliath and Goldlund gold projects. These activities include:

Completion of an economic evaluation of a Goliath plus Goldlund scenario. Technical studies are underway to support this analysis, including plant and processing facilities, mining optimization, and an evaluation of potential operations at Goliath (underground and open pit) combined with Goldlund open pit mining scenarios. Future technical studies are also anticipated to include an optimization of the tailings storage facilities to review potential efficiencies that may be gained from developing the two projects in tandem. Results of this study are anticipated in late 2020.The commencement of a 25,000-metre drill program. Drilling at Goldlund will be focused on infill and expansion starting with Zone 1, 4 and 8. At Goliath, drilling will continue to focus on potential expansion of the east C Zone within the resource area in addition to exploration drilling on the prospective regional targets recently identified through IP and soil sample programs.Environmental baseline collect ion commenced to assist with the development and permitting activities for Goldlund. Treasury Metals has also engaged additional support to assist with ongoing permitting efforts at Goliath and continues to engage and discuss operational and development plans with regional Indigenous communities, the public, and local stakeholders.

Early Warning Disclosure

Treasury Metals was incorporated under the laws of the Province of Ontario under the Business Corporations Act (Ontario) The head office of Treasury Metals is located at the Exchange Tower, 130 King Street West, Suite 3680, Box 99, Toronto, Ontario M5X 1B1. The TML Common Shares are traded on the Toronto Stock Exchange ("TSX").

First Mining is a Canadian mineral exploration and development company incorporated under the laws of British Columbia. First Mining's head office is located at the following address Suite 2070 - 1188 West Georgia Street, Vancouver, British Columbia, V6E 4A2.

Pursuant to the Transaction, First Mining acquired: (i) 130 million TML Common Shares; (ii) 35 million Warrants , with each Warrant entitling the holder thereof to purchase one TML Common Share at an exercise price of $0.50 for a period of 36 months. Prior to the Transaction, First Mining held no Shares and no Warrants.

As a result of the Transaction, First Mining's ownership interest in Treasury Metals increased to 130 million TML Common Shares, representing approximately 43% of the Shares outstanding on a non-diluted basis, based on the number of Shares issued and outstanding immediately following the completion of Transaction.

Assuming the full exercise of the Warrants, an aggregate of 165 million TML Common Shares would be owned by First Mining, which would represent approximately 49% of the TML Shares outstanding, based on the number of Shares issued and outstanding immediately following the completion of Transaction, and including TML Common Shares issuable on exercise of the Warrants.

Following the Transaction, on receipt of necessary regulatory approvals, Treasury Metals will consolidate its common shares on a 3 to 1 basis (the "Consolidation"). The Warrants and Shares issuable to First Mining pursuant to the Share Purchase Agreement will be adjusted in accordance with the Consolidation. The numbers in this press release are expressed on a pre-Consolidation basis unless otherwise stated.

First Mining's decision to complete the Transaction was made in the context of its overall investment purposes. First Mining will continue to review its investment alternatives from time to time and may determine to increase or decrease its equity ownership in Treasury Metals through the acquisition or sale of additional outstanding common shares or other securities of Treasury Metals, either through open market or privately negotiated transactions in accordance with applicable securities laws.

To obtain a copy of the early warning report please contact Spiros Cacos, Vice President, Investor Relations at the contact information set out below.

Advisors and Counsel

Cormark Securities Inc. acted as financial advisor to First Mining. Blake, Cassels & Graydon LLP acted as Canadian legal counsel to First Mining, and Dorsey & Whitney LLP acted as U.S. legal counsel to First Mining.

Qualified Person

Hazel Mullin, P.Geo., Director, Data Management and Technical Services of First Mining, is a "Qualified Person" for the purposes of National Instrument 43-101 Standards of Disclosure for Mineral Projects ("NI 43-101"), and she has reviewed and approved the scientific and technical disclosure contained in this news release.

About First Mining Gold Corp.

First Mining is a Canadian gold developer focused on the development and permitting of the Springpole Gold Project in northwestern Ontario. Springpole is one of the largest undeveloped gold projects in Canada, currently hosting a mineral resource base of 4.67 million ounces of gold in the Indicated category and 0.23 million ounces of gold in the Inferred category1. A Pre-Feasibility Study is underway, with completion targeted in early 2021, and permitting is on-going with submission of the Environmental Impact Statement targeted for 2021. The Company also holds a large equity position in Treasury Metals who are advancing the Goldlund-Goliath gold projects in Ontario towards construction. First Mining's portfolio of gold projects in eastern Canada also includes the Pickle Crow (being advanced in partnership with Auteco Minerals Ltd.), Cameron, Hope Brook, Duparquet, Duquesne, and Pitt gold project s.

First Mining was created in 2015 by Mr. Keith Neumeyer, founding President and CEO of First Majestic Silver Corp.

ON BEHALF OF FIRST MINING GOLD CORP.

Daniel W. WiltonChief Executive Officer and Director

For further information, please contact:

Spiros Cacos | Vice President, Investor RelationsDirect: +1 604 639 8825 | Toll Free: 1 844 306 8827 | Email: info@firstmininggold.comwww.firstmininggold.com

Note:

1. These numbers are from the independent technical report titled "Preliminary Economic Assessment Update for the Springpole Gold Project, Ontario, Canada", dated November 5, 2019, which was prepared by SRK Consulting (Canada) Inc. in accordance with National Instrument 43-101 Standards of Disclosure for Mineral Projects ("NI 43-101") and is available at www.sedar.com under First Mining's SEDAR profile. Readers are cautioned that the PEA is preliminary in nature, it includes inferred mineral resources that are considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized as mineral reserves, and there is no certainty that the PEA will be realized.

Cautionary Note Regarding Forward-Looking Statements

This news release includes certain "forward-looking information" and "forward-looking statements" (collectively "forward-looking statements") within the meaning of applicable Canadian and United States securities legislation including the United States Private Securities Litigation Reform Act of 1995. These forward-looking statements are made as of the date of this news release. Forward-looking statements are frequently, but not always, identified by words such as "expects", "anticipates", "believes", "plans", "projects", "intends", "estimates", "envisages", "potential", "possible", "strategy", "goals", "objectives", or variations thereof or stating that certain actions, events or results "may", "could", "would", "might" or "will" be taken, occur or be achieved, or the negative of any of these terms and similar expressions.

Forward-looking statements in this news release relate to future events or future performance and reflect current estimates, predictions, expectations or beliefs regarding future events and include, but are not limited to, statements with respect to: (i) the advancement of a combined Goliath-Goldlund gold project towards construction and the upside potential of such a combined gold project; (ii) the Company's plans to distribute 70 million TML Shares and all 35 million TML Warrants to the Company's shareholders and the timing for completion of such distribution; (iii) timing for Treasury Metals to complete a preliminary economic assessment on a combined Goliath-Goldlund gold project and to carry out future technical studies on the combined project; (iv) the 25,000-metre drill program at the combined Goliath-Goldlund gold project and any plans for Treasury Metals to continue drilling at Goliath and Goldlund and the potential for resource growth and future exploration success fr om all such drill programs; (v) any milestone-based payments due to the Company under the Transaction; (vi) the Company's rights to nominate individuals to the Treasury Board under the Investor Rights Agreement; (vii) timing for the formation of the Technical Committee; (viii) timing for the completion of a Pre-Feasibility Study for Springpole; (ix) timing for the submission of an Environmental Impact Statement for Springpole; and (x) realizing the value of the Company's gold projects for the Company's shareholders. All forward-looking statements are based on First Mining's or its consultants' current beliefs as well as various assumptions made by them and information currently available to them. There can be no assurance that such statements will prove to be accurate, and actual results and future events could differ materially from those anticipated in such statements. Forward-looking statements reflect the beliefs, opinions and projections on the date the statements are made and are based upon a number of assumptions and estimates that, while considered reasonable by the respective parties, are inherently subject to significant business, economic, competitive, political and social uncertainties and contingencies. Many factors, both known and unknown, could cause actual results, performance or achievements to be materially different from the results, performance or achievements that are or may be expressed or implied by such forward-looking statements and the parties have made assumptions and estimates based on or related to many of these factors. Such factors include, without limitation: the presence of and continuity of metals at Goldlund at estimated grades; success in realizing drilling programs; fluctuations in the spot and forward price of gold, silver, base metals or certain other commodities; fluctuations in the currency markets (such as the Canadian dollar versus the U.S. dollar); changes in national and local government, legislation, taxation, cont rols, regulations and political or economic developments; risks and hazards associated with the business of mineral exploration and exploration drilling programs, development and mining (including environmental hazards, industrial accidents, unusual or unexpected formations, pressures, cave-ins and flooding); the presence of laws and regulations that may impose restrictions on mining; employee relations; relationships with and claims by local communities, indigenous populations and other stakeholders; availability and increasing costs associated with mining inputs and labour; the speculative nature of mineral exploration and development; title to properties.; and the additional risks described in the Company's Annual Information Form for the year ended December 31, 2019 filed with the Canadian securities regulatory authorities under the Company's SEDAR profile at www.sedar.com, and in the Company's Annual Report on Form 40-F filed with the SEC on EDGAR.

First Mining cautions that the foregoing list of factors that may affect future results is not exhaustive. When relying on our forward-looking statements to make decisions with respect to First Mining, investors and others should carefully consider the foregoing factors and other uncertainties and potential events. First Mining does not undertake to update any forward-looking statement, whether written or oral, that may be made from time to time by the Company or on our behalf, except as required by law.

Cautionary Note to United States Investors

This news release has been prepared in accordance with the requirements of the securities laws in effect in Canada, which differ from the requirements of U.S. securities laws. Unless otherwise indicated, all resource and reserve estimates included in this news release have been prepared in accordance with NI 43-101 and the Canadian Institute of Mining, Metallurgy, and Petroleum 2014 Definition Standards on Mineral Resources and Mineral Reserves. NI 43-101 is a rule developed by the Canadian Securities Administrators which establishes standards for all public disclosure an issuer makes of scientific and technical information concerning mineral projects. Canadian standards, including NI 43-101, differ significantly from the requirements of the SEC, and mineral resource and reserve information contained herein may not be comparable to similar information disclosed by U.S. companies. In particular, and without limiting the generality of the foregoing, the term "resource" does not equate to the term "reserves". Under U.S. standards, mineralization may not be classified as a "reserve" unless the determination has been made that the mineralization could be economically and legally produced or extracted at the time the reserve determination is made. The SEC's disclosure standards normally do not permit the inclusion of information concerning "measured mineral resources", "indicated mineral resources" or "inferred mineral resources" or other descriptions of the amount of mineralization in mineral deposits that do not constitute "reserves" by U.S. standards in documents filed with the SEC. Investors are cautioned not to assume that any part or all of mineral deposits in these categories will ever be converted into reserves. U.S. investors should also understand that "inferred mineral resources" have a great amount of uncertainty as to their existence and great uncertainty as to their economic and legal feasibility. It cannot be assumed that all or any part of an " inferred mineral resource" will ever be upgraded to a higher category. Under Canadian rules, estimated "inferred mineral resources" may not form the basis of feasibility or pre-feasibility studies except in rare cases. Investors are cautioned not to assume that all or any part of an "inferred mineral resource" exists or is economically or legally mineable. Disclosure of "contained ounces" in a resource is permitted disclosure under Canadian regulations; however, the SEC normally only permits issuers to report mineralization that does not constitute "reserves" by SEC standards as in-place tonnage and grade without reference to unit measures. The requirements of NI 43-101 for identification of "reserves" are also not the same as those of the SEC, and reserves reported by the Company in compliance with NI 43-101 may not qualify as "reserves" under SEC standards. Accordingly, information concerning mineral deposits set forth herein may not be comparable with information made public by c ompanies that report in accordance with U.S. standards.

SOURCE: First Mining Gold Corp.