Onyx Announces Upsize Of Brokered Financing To $18 Million And Concurrent $5.6 Million Non-Brokered Financing At $2.43 Per Share Involving Strategic Investors

(MENAFN- Newsfile Corp) Vancouver, British Columbia--(Newsfile Corp. - September 17, 2025) - Onyx Gold Corp. (TSXV: ONYX) (OTCQX: ONXGF) ("Onyx" or the "Company") is pleased to announce that, in connection with its previously announced $15,000,000 "bought deal" private placement, Cormark Securities Inc., together with Canaccord Genuity Corp. on behalf of a syndicate of underwriters (collectively, the " Underwriters "), have agreed with the Company to increase the size of the "bought deal" private placement by approximately $3,000,000 for gross aggregate proceeds of $18,000,000 (the " Offering ").

The Company is also pleased to announce a concurrent non-brokered private placement priced at $2.43 per NB FT Share (as defined below) for gross aggregate proceeds of approximately $5,600,000 (the " Non-Brokered Private Placement "), involving strategic investors. Between the Offering and the Non-Brokered Private Placement, the Company expects to raise aggregate gross proceeds of approximately $23,600,000 (or approximately $25,600,000 if the Option (as defined below) is exercised in full).

The Offering

The Offering will consist of the issuance and sale of: (i) 4,740,000 common shares of the Company that will each qualify as "flow-through shares" (within the meaning of subsection 66(15) of the Income Tax Act (Canada)) (the " FT Shares "), at a price of $2.11 per FT Share, for gross proceeds of $10,001,400, and (ii) 5,332,400 common shares of the Company (the " HD Shares ") at a price of $1.50 per HD Share, for gross proceeds of $7,998,600, for aggregate gross proceeds to the Company of $18,000,000.

In addition, the Company has granted the Underwriters an option (the " Option ") to further increase the size of the Offering by up to an additional $2,000,000 (through the issuance and sale of an additional number of FT Shares, HD Shares or a combination thereof), on the same terms and conditions as the Offering, by giving written notice of the exercise of the Option, or a part thereof, to the Company at any time up to 48 hours prior to the Closing Date (as defined below). Unless the context otherwise requires, all references to the Offering shall include any FT Shares and/or HD Shares issued in connection with the exercise of the Option.

The Company will use an amount equal to the gross proceeds from the sale of the FT Shares, pursuant to the provisions in the Income Tax Act (Canada) (the " Tax Act "), to incur (or be deemed to incur) eligible "Canadian exploration expenses" that qualify as "flow-through mining expenditures" (as both terms are defined in the Tax Act) (the " Qualifying Expenditures ") related to the Company's projects in Ontario, on or before December 31, 2026, and to renounce all the Qualifying Expenditures in favour of the subscribers of the FT Shares effective December 31, 2025. If the Qualifying Expenditures are reduced by the Canada Revenue Agency or the Company is unable to renounce the Qualifying Expenditures, the Company will indemnify each subscriber of FT Shares, as applicable, for any additional taxes payable by such subscriber as a result of the Company's failure to renounce the Qualifying Expenditures as agreed.

The net proceeds from the sale of the HD Shares will be used by the Company for exploration of its mineral properties and general corporate purposes.

The Offering is expected to close on or about October 2, 2025 (the " Closing Date "), or such other date as the Company and the Underwriters may agree and is subject to certain conditions including, but not limited to, the receipt of all necessary regulatory and other approvals including the conditional approval of the TSX Venture Exchange.

Subject to compliance with applicable regulatory requirements and in accordance with National Instrument 45-106 - Prospectus Exemptions (" NI 45-106 "), the FT Shares and HD Shares will be offered for sale to purchasers resident in all Provinces of Canada and/or other qualifying jurisdictions pursuant to the listed issuer financing exemption under Part 5A of NI 45-106 (the " Listed Issuer Financing Exemption ") as amended and supplemented by Coordinated Blanket Order 45-935 Exemptions from Certain Conditions of the Listed Issuer Financing Exemption. The FT Shares and HD Shares issued under the Listed Issuer Financing Exemption will not be subject to a hold period pursuant to applicable Canadian securities laws.

An amended offering document related to the Offering and the use by the Company of the Listed Issuer Financing Exemption can be accessed under the Company's profile on SEDAR+ at and on the Company's website at . Prospective investors should read this offering document before making an investment decision.

The Non-Brokered Private Placement

The Non-Brokered Private Placement will consist of the sale and issuance of the issuance of 2,300,000 common shares in the capital of the Company that will each qualify as "flow-through shares" (within the meaning of subsection 66(15) of the Tax Act) (the " NB FT Shares "), at a price of $2.43 per NB FT Share, for aggregate gross proceeds of $5,589,000.

The Company will use an amount equal to the gross proceeds from the sale of the NB FT Shares, pursuant to the provisions in the Tax Act, to incur (or be deemed to incur) Qualifying Expenditures related to the Company's projects in Ontario, on or before December 31, 2026, and to renounce all the Qualifying Expenditures in favour of the subscribers of the NB FT Shares effective December 31, 2025. If the Qualifying Expenditures are reduced by the Canada Revenue Agency or the Company is unable to renounce the Qualifying Expenditures, the Company will indemnify each subscriber of NB FT Shares, as applicable, for any additional taxes payable by such subscriber as a result of the Company's failure to renounce the Qualifying Expenditures as agreed.

The Non-Brokered Private Placement is expected to close on or about the Closing Date, or such other date as the Company and the subscribers may agree, and is subject to certain conditions to closing, including the conditional approval of the TSX Venture Exchange.

The NB FT Shares will be offered pursuant to applicable exemptions from the prospectus requirements under applicable securities laws and will be subject to a hold period of four months and one day from the date of issuance in accordance with applicable Canadian securities laws. No finder's fees are payable in connection with the Non-Brokered Private Placement.

This news release does not constitute an offer to sell or a solicitation of an offer to buy nor shall there be any sale of any of the securities in any jurisdiction in which such offer, solicitation or sale would be unlawful, including any of the securities in the United States of America. The securities have not been and will not be registered under the United States Securities Act of 1933, as amended (the " 1933 Act ") or any state securities laws and may not be offered or sold within the United States or to, or for account or benefit of, U.S. persons unless registered under the 1933 Act and applicable state securities laws, or an exemption from such registration requirements is available. "United States" and "U.S. person" have the meaning ascribed to them in Regulation S under the 1933 Act.

About Onyx Gold

Onyx Gold Corp. is a Canadian exploration company focused on well-established mining jurisdictions, with assets in Timmins, Ontario, and Yukon Territory. In Timmins, the Company holds a 100% interest in a district-scale portfolio totaling more than 443 km2 across three projects: the Munro-Croesus Gold Property (109 km2), Golden Mile (140 km2), and Timmins South (194 km2). All projects are accessible year-round via existing road networks and benefit from close proximity to regional infrastructure.

In Yukon, Onyx controls four properties in the emerging Selwyn Basin, an area of growing exploration significance following several recent discoveries. Guided by an experienced board and management team, Onyx Gold is dedicated to creating shareholder value through discovery, disciplined capital allocation, and a commitment to responsible and sustainable mineral exploration.

On Behalf of Onyx Gold Corp.

" Brock Colterjohn "
President & CEO

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