Onyx Gold Closes Strategic Acquisition of the Lalonde Property in Timmins, Ontario

Vancouver, April 18, 2024 - Onyx Gold Corp. (TSXV: ONYX) (OTCQX: ONXGF) is pleased to announce that it has completed the previously announced acquisition of the Lalonde Property (the "Property") located east of Timmins, Ontario (see Company news release dated January 30^th, 2024).

The Property expands the Munro-Croesus Property ("Munro-Croesus" or the "Project") to 9,235 hectares ("ha"), a 32% increase (Figure 1). This adds substantial exploration potential across this relatively underexplored yet highly prospective section of the Timmins Gold Camp. The Property is contiguous and on strike with Munro-Croesus and is host to multiple high-grade gold occurrences.

The Acquisition cost for 100% ownership was 400,000 shares and C$20,000 (a total value of $93,000 based on the Company's 20-day volume-weighted average price at the time the agreement was announced). The Property is subject to underlying NSR royalties of 2.0% owned by a third party.

Highlights of the Lalonde Property and the Agreement:

• Large (2,235 ha) land package (Figure 2) contiguous and on strike to Munro-Croesus and directly north of Mayfair Gold's 3.5 Moz Au Fenn-Gib Deposit ¹.

• +10 near-surface gold prospects and occurrences with gold values ranging from 1.03 grams per tonne ("g/t") gold ("Au") to 41.1 g/t Au, 57.8 g/t Au, and 2,500 g/t Au².

• The C Zone, the most advanced prospect on the Property, returned spectacular coarse-grain gold in quartz veins from a blasted trench grading up to 2,500 g/t Au (Plate 1). This high-grade vein has characteristics similar to the nearby historic Croesus Mine, indicating the potential for more 'Croesus-like' veins on the Property.

• There has been limited work done on the Property since the 1980s, with the last work done in 2011.

• Excellent access to the Property with paved Highway 101 passing near the southern boundary

"The Lalonde Property is a great addition to our Munro-Croesus Project," said Brock Colterjohn, President & CEO. "It significantly increases Onyx's landholdings in the district, underscoring the Company's commitment to maximizing its presence and potential in the Timmins Gold Camp. We see excellent potential for additional mineral discoveries on the Property, which has seen no exploration work since 2011. In our view, the work completed to date has only scratched the surface of the Property's potential, and we look forward to starting work there this summer."

2024 Summer Work Program

Onyx is planning a maiden summer field program consisting of mechanized stripping, sampling, field mapping, and prospecting to validate the +10 known gold prospects and generate new prospective targets. The information generated from this program will help prioritize drill targets ahead of a potential drill program later this year.

Figure 1 - Munro-Croesus Property Top Gold Targets

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Figure 2 - Munro-Croesus Property Geology and Lalonde Acquisition

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Plate 1 - Coarse Gold in Blasted Vein Samples from C Zone (2,500 g/t Au)

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About the Munro-Croesus Project

The Munro-Croesus Project is located along Highway 101 in the heart of the Abitibi greenstone belt, Canada's premier gold mining jurisdiction. This large, 100% owned land package includes the past-producing Croesus Gold Mine, which yielded some of the highest-grade gold ever mined in Ontario. Extensive land consolidation from 2020-2023 has unified the patchwork of patented and unpatented mining claims surrounding the Croesus Gold Mine into one coherent package (Figure 1) and enhanced the exploration potential of the Project. The Project covers 92 km² of highly prospective geology within the influence of major gold-bearing structural breaks. Bulk-tonnage gold deposits located in the immediate region include the Fenn-Gib gold project being developed by Mayfair Gold Corp. that contains an Indicated Resource of 3.38 Moz at 0.93 g/t Au and an Inferred Resource of 157 koz at 0.85 g/t Au, and the Tower Gold Project being developed by Moneta Gold Inc. that contains an open pit Indicated Resource of 4.46 Moz at 0.92 g/t Au and an Inferred Resource of 8.29 Moz at 1.09 g/t Au¹.

About the Timmins Area Gold Properties

Onyx owns 100% of its three Timmins properties, totaling 420 km² in size. The Munro-Croesus Gold Project is located approximately 75 kilometers (47 miles) east of Timmins, proximal to the Porcupine-Destor and Pipestone Faults, and approximately two kilometers (1.2 miles) northwest and along trend of Mayfair Gold Corp.'s multi-million ounce Fenn-Gib gold deposit. Mining occurred intermittently at Munro-Croesus between 1915 and 1936. The Golden Mile 140 square kilometer (54 square miles) property is located nine kilometers (5.6 miles) northeast of Newmont's multi-million-ounce Hoyle Pond deposit in Timmins. The Timmins South (Golden Perimeter) 187 square kilometers (72 square miles) property is located to the south and southeast of Timmins and surrounds the Shaw dome structure.

About Onyx Gold

Onyx Gold is an exploration company focused on well-established Canadian mining jurisdictions, with assets in Timmins, Ontario, and Yukon Territory. The Company's extensive portfolio of quality gold projects in the greater Timmins gold camp includes the Munro-Croesus Gold property, renowned for its high-grade mineralization, plus two additional earlier-stage large exploration properties, Golden Mile and Timmins South. Onyx Gold also controls four properties in the Selwyn Basin area of Yukon Territory, which is currently gaining significance due to recent discoveries in the area. Onyx Gold's experienced board and senior management team are committed to creating shareholder value through the discovery process, careful allocation of capital, and environmentally/socially responsible mineral exploration.

Qualified Person and Quality Assurance

Ian Cunningham-Dunlop, P.Eng., Executive Vice President for Onyx Gold Corp. and a qualified person ("QP") as defined by Canadian National Instrument 43-101, has reviewed and approved the technical information contained in this release.

On Behalf of Onyx Gold Corp.

"Brock Colterjohn"

President & CEO

For further information, please visit the Onyx Gold Corp. website at www.onyxgold.com or contact:

Brock Colterjohn, President & CEO
or
Nicole Hoeller, VP of Corporate Communications

Phone: 1-604-629-1165 or North American toll-free 1-855-629-1165
Email: nicole@onyxgold.com or information@onyxgold.com.

Website: www.onyxgold.com
LinkedIn: https://www.linkedin.com/company/onyx-gold-corp/?viewAsMember=true
Twitter: https://twitter.com/OnyxGoldCorp

1. Fenn-Gib Gold Project and Tower Gold Project mineral resources compiled from public sources and are provided for general information purposes. Readers are cautioned that the Company has no interest in or right to acquire any interest in adjacent properties and they are not indicative of mineral deposits on the Company's properties or any potential exploration thereof.

2. The QP has been unable to verify any of the historical technical information in this release and this information is not necessarily indicative of additional mineralization occurring on the Property. Interested parties are referred to Brunswick Resources Inc. Annual Management's Discussion and Analysis Report for the year ended December 31, 2015 as well as the Ontario Ministry of Mines Assessment File Database and the Mineral Inventory Database.

Forward looking information: This news release includes certain "forward-looking information" within the meaning of Canadian securities legislation and "forward-looking statements" within the meaning of the United States Private Securities Litigation Reform Act of 1995 (collectively "forward looking statements").

Forward-looking statements include predictions, projections, and forecasts and are often, but not always, identified by the use of words such as "seek", "anticipate", "believe", "plan", "estimate", "forecast", "expect", "potential", "project", "target", "schedule", "budget" and "intend" and statements that an event or result "may", "will", "should", "could" or "might" occur or be achieved and other similar expressions and includes the negatives thereof. All statements other than statements of historical fact included in this release, including, without limitation, statements regarding the Company's planned exploration programs and drill programs and potential significance of results including the new high-grade vein structure at the Munro Croesus property described above, are forward-looking statements that involve various risks and uncertainties. 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 are based on a number of material factors and assumptions. Important factors that could cause actual results to differ materially from Company's expectations include actual exploration results, changes in project parameters as plans continue to be refined, results of future resource estimates, future metal prices, availability of capital, and financing on acceptable terms, general economic, market or business conditions, uninsured risks, regulatory changes, defects in title, availability of personnel, materials, and equipment on a timely basis, accidents or equipment breakdowns, delays in receiving government approvals, unanticipated environmental impacts on operations and costs to remedy same, and other exploration or other risks detailed herein and from time to time in the filings made by the Company with securities regulators. Although the Company has attempted to identify important factors that could cause actual actions, events, or results to differ from those described in forward-looking statements, there may be other factors that cause such actions, events, or results to differ materially from those anticipated. There can be no assurance that forward-looking statements will prove to be accurate, and accordingly readers are cautioned not to place undue reliance on forward-looking statements.

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