First Mining Announces 2025 Third Quarter Financial Results and Operating Highlights

Press Release

November 13, 2025 – Vancouver, Canada – First Mining Gold Corp. (“First Mining” or the “Company”) (TSX: FF) (OTCQX: FFMGF) (FRANKFURT: FMG) reports its third quarter financial results for the quarter ended September 30, 2025. The financial statements and management’s discussion and analysis (“MD&A”) are available on First Mining’s website at www.firstmininggold.com/investors/reports-filings/financials/ and have been posted under the Company’s profile on SEDAR+ at www.sedarplus.ca and EDGAR at www.sec.gov.

Q3 2025 Highlights:

• On July 3, 2025, Mishkeegogamang First Nation and the Company announced that they signed a Long-Term Relationship Agreement (“Agreement” or “LTRA”) covering the Springpole Gold Project, located in northwestern Ontario. The Agreement sets out a collaborative approach for the development of one of Canada’s largest gold resources, through construction, operations, and closure, in a manner that respects the environment and provides direct benefits to the First Nation.
• On July 22, 2025, the Company closed an upsized marketed public offering of 66,670,000 units for total gross proceeds of $12,000,600 (the “Public Offering”).  On August 5, 2025, the Company closed an upsized non-brokered offering of 95,000,000 units for proceeds of $17,100,000 and 33,350,000 flow-through units for proceeds of $7,337,000 (the “Non-Brokered Offering”). The total proceeds of the Non-Brokered Offering and Public Offering was $36,437,600.
• On July 31, 2025, the Company sold its remaining 20% project interest in the Hope Brook Gold Project for total consideration comprised of $3 million in cash and 7 million common shares of Big Ridge.
• On September 8, 2025, the Company announced additional drilling results from the 2025 exploration program at Duparquet. Highlights from the drilling include the continued advancement of the Aiguille discovery zone. Drill hole DUP25-058 returned 1.43 g/t Au over 24.1m, including 4.56 g/t Au over 4.0m, further extending the target eastward along strike.
• On September 18, 2025, the Company announced the signing of a historic Memorandum of Understanding with the City of Duparquet to support Community Development and Collaboration on the Duparquet Gold Project.
• On September 24, 2025, the Company announced results from the 2025 Duparquet drilling program with the expansion of the newly discovered Miroir Target with drill hole DUP25-064 Returning 3.23 g/t Au over 25.9m. On November 10, 2025, the Company announced additional results at the Miroir target including Drill hole DUP25-078 returning 2.01 g/t Au over 29.8 m, including 15.70 g/t Au over 0.75 m and 18.20 g/t Au over 1.0 m.
• Lisa Peterson, CPA, CA, will resume her role as the Company’s Chief Financial Officer (“CFO”) following the completion of her maternity leave, effective November 14, 2025. During her absence, Darren Prins, CPA, CA, served as Interim CFO of the Company and Richard Huang, the Company’s Vice President, Corporate Development, was appointed Corporate Secretary, in addition to his current role, effective April 1, 2025.
• First Mining is pleased to announce that Vincy Benjamin will be joining the Company as Director of Projects effective November 24, 2025.  Mr. Benjamin was previously Director of Engineering & Construction for Skeena Resources and prior to that, Director of Projects for Sabina Gold & Silver. He brings 25 years of experience leading the full lifecycle of major capital projects from feasibility and financing through construction, commissioning, and operational handover.
• During the quarter, the Company continued engagement with local and Indigenous communities around the Springpole Gold Project while advancing responses to comments in the Federal and Provincial Environmental Assessment processes.
• As of September 30, 2025, the Company’s cash and marketable securities balance was $37.6 million and the equity interest in PC Gold Inc. (Pickle Crow Project) was $21.5 million.

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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