First Mining Announces Receipt of $6 Million in Proceeds from Warrants Exercise

Press Release

December 16, 2025 – Vancouver, Canada – First Mining Gold Corp. (“First Mining” or the “Company”) (TSX: FF) (OTCQX: FFMGF) (FRANKFURT: FMG) is pleased to announce that it has received total proceeds of C$6,410,045 from the exercise by First Majestic Silver Corp. (“First Majestic”) of 32,050,228 common share purchase warrants of the Company (the “Warrants”) at a price of $0.20 per Warrant.  The Warrants were issued in relation to amending the terms of a silver purchase agreement among First Majestic, First Mining and Gold Canyon Resources Inc., a wholly-owned subsidiary of First Mining.

The Company intends to use the proceeds from the exercise of these Warrants to advance First Mining’s Springpole and Duparquet gold projects, as well as for general working capital and corporate purposes.

Following the exercise of the Warrants, First Majestic’s ownership in First Mining increases to 47,379,944 common shares representing 3.5% of the total common shares of the Company outstanding.

About First Mining Gold Corp.

First Mining is a gold developer advancing two of the largest gold projects in Canada, the Springpole Gold Project in northwestern Ontario, where we have commenced a Feasibility Study and permitting activities are on-going with a final Environmental Impact Statement / Environmental Assessment for the project submitted in November 2024, and the Duparquet Gold Project in Quebec, a PEA-stage development project located on the Destor-Porcupine Fault Zone in the prolific Abitibi region. First Mining also owns the Cameron Gold Project in Ontario and a 30% project interest in the Pickle Crow Gold Project.

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

ON BEHALF OF FIRST MINING GOLD CORP.

Daniel W. Wilton
Chief Executive Officer and Director

For further information, please contact:

Toll Free: 1 844 306 8827 | Email: info@firstmininggold.com
Paul Morris | Director, Investor Relations | Email: paul@firstmininggold.com

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