Great Atlantic Advances 2026 Plans for Its Keymet High-Grade Silver District: Two Historic Silver Mines, Including the Keymet Silver Mine (Closed Due to Fire), 1,100 g/t Silver Over 3 Meters Recently Drilled by Great Atlantic - Northern New Brunswick

Vancouver, December 10, 2025 - Great Atlantic Resources Corp. (TSXV: GR) (the "Company" or "Great Atlantic") is pleased to announce it has completed a compilation of reported exploration results for silver at its 100% owned Keymet Precious - Base Metal Project, located in northeast New Brunswick.

HIGHLIGHTS OF THIS COMPILATION INCLUDE:

• 19th-century workings at the Elmtree Silver Mine occurrence (circa 1880-1897);
• Commercial silver-lead-zinc-copper production from the Keymet Mine (mid 1950s); and
• Multiple high-grade silver intercepts from Great Atlantic 2015-2021 diamond drilling, including up to 1,158 grams / tonne (g/t) silver.

Vein with semi-massive sulfides - Ky-18-14 (1,158 g/t Ag over 3.00 meters core length)

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The Keymet Project consists of two mineral claims covering a total area of approximately 3,340 hectares, located approximately 20 kilometers northwest of Bathurst.

The compilation has identified multiple reported silver bearing veins / vein systems within the northern region of the project, including at the historic Keymet Mine and Elmtree Silver Mine occurrence and other polymetallic veins / vein systems (New Brunswick Department of Natural Resources and Energy Development, Mineral Occurrence Database). Collectively, the information demonstrates that Keymet is one of the most historically significant silver-bearing vein systems in Atlantic Canada, with multiple silver bearing vein structures being targets for exploration.

"Our renewed focus on the silver potential at Keymet is revealing a rich and layered mining history dating back nearly 150 years. Few projects in Atlantic Canada can show both 19th-century silver workings and 1950s commercial production, combined with modern high-grade drill results exceeding one kilogram per tonne silver," states Mr. Anderson, CEO.

"The same mineralized structures exploited in the 1800s and 1950s remain vastly underexplored. The compilation demonstrates the strong geological continuity and the potential for additional high-grade silver veins. This places Great Atlantic in a unique discovery position in Eastern Canada."

Keymet Property Map

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19TH-CENTURY SILVER WORKINGS - ELMTREE SILVER MINE:

Provincial mineral occurrence database records document silver-lead-zinc-bearing veins in the northwest region of the Keymet Project with reported exploration dating back to the 1880s. Workings at the historic Elmtree Silver Mine (also referred to as the Elmtree 13 mineral occurrence - New Brunswick Department of Natural Resources and Energy Development Mineral Occurrence Database, Reference No. 901) reportedly include a shaft to approximately 20 metres depth, developed on a vein with quartz , calcite and sulfides reported to be 1.8-2.4 metres wide. Reported assays at that time included an assay of 33.75 oz/ton silver. Great Atlantic completed three drill holes in this general area during 2015 and 2023. A 0.51-meters long (core length) sample from hole Ky-15-01 returned 9.53% zinc, 9.01% lead and 66 g/t silver.

1954-1956 KEYMET MINE PRODUCTION (SILVER-LEAD-ZINC-COPPER):

The past-producing Keymet Mine, located in the northwest region of the Keymet Project, was developed on polymetallic veins and operated during the mid-1950s (New Brunswick Department of Natural Resources and Energy Development Mineral Occurrence Database, Reference No. 368). The New Brunswick Mineral Occurrence Database files report development to the 900-foot level (274 meters) and production during 1954-1956 of approximately 59,000 tons grading on average 33.9 g/t silver, 2.59% zinc, 2.44% lead and 0.25% copper. Operation ceased during 1956 following a surface fire.

Historic Keymet Base Metal - Silver Mine (1950s)- burnt down and was never recapitalized

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GREAT ATLANTIC TRENCHING AND DIAMOND DRILLING - CONFIRMATION OF HIGH-GRADE SILVER:

Great Atlantic's diamond drilling at and near the Elmtree 12 polymetallic vein system during 2015-2021 included multiple significant silver intercepts including (core length) (see Great Atlantic website for New Releases):

• Ky-18-14: 3.00m at 1,158 g/t Ag, 9.04% Zn, 9.19% Cu and 2.16% Pb
• Ky-17-8: 1.27m at 576 g/t Ag, 18.80% Zn, 3.55% Cu and 1.16% Pb
• Ky-18-16: 0.52m at 478 g/t Ag, 4.47% Zn and 7.85% Cu
• Ky-18-10: 1.00m at 223 g/t Ag, 16.80% Zn and 1.60% Cu
• Ky-17-6: 4.95m at 209 g/t Ag, 7.67% Zn and 1.57% Cu
• Ky-17-5: 0.80m at 166 g/t Ag, 13.65% Zn and 1.20% Cu
• Ky-18-12: 1.20m at 157 g/t Ag, 8.90% Zn and 3.81% Cu
• Ky-15-3: 1.80m at 152 g/t Ag, 16.68% Zn and 1.11% Cu

2015-2018 Drill Hole Plan Map - Elmtree 12 Occurrence Area

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The Elmtree 12 occurrence is located in the northwest region of the Keymet Project, northwest of the Keymet Mine (New Brunswick Department of Natural Resources and Energy Development Mineral Occurrence Database, Reference No. 951).

Trenching by Great Atlantic during 2015 at the Elmtree 12 vein system exposed glacial float and veins in bedrock with high grade silver. A 0.5-meters long channel sample within one trench returned 308 g/t silver, 1.94% copper and 1.52% zinc. A sample from a piece of glacial float in the same trench returned 472 g/t silver, 7.6% zinc and 5.1% copper.

Five additional mineral occurrences with reported silver are reported within the northern region of the Keymet Project. These include (with reference numbers as per the New Brunswick Department of Natural Resources and Energy Development Mineral Occurrence Database):

• Elmtree 2 (114)
• Elmtree 6 (110)
• Elmtree 14 (834)
• Keymet 3 (921)
• Madran Northeast (1513)

Keymet Claim Location Map

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At the Elmtree 2 occurrence a 1965 drill hole was reported to intersect 2.0 oz. / ton silver, 5.86% zinc and 3.38% lead over 0.3 meters core length (New Brunswick Department of Natural Resources and Energy Development, Mineral Report of Work No. 470461). This occurrence is reported within the northwest region of the Keymet Project, northwest of the Keymet Mine. At the Elmtree 6 occurrence a 1960 grab sample was reported to return 4.52 oz. / ton silver, 7.41% zinc and 5.85% lead (New Brunswick Department of Natural Resources and Energy Development, Mineral Report of Work No. 470052, Wark, 1964). Both the Elmtree 2 and Elmtree 6 occurrences are located in the northwest region of the Keymet Project, northwest of the Keymet Mine. Great Atlantic has not confirmed mineralization at the Elmtree 2, Elmtree 6, Elmtree 14, Keymet 3 or Madran Northeast occurrences.

CONCLUSIONS BY GREAT ATLANTIC MANAGEMENT:

Based on the multi-generation dataset (historic records, underground plans, diamond drilling, trenching, geophysics and geochemistry), Great Atlantic concludes that:

• The Keymet Project hosts at least two historically exploited silver-rich vein systems (Elmtree Silver Mine and Keymet Mine);
• Multiple silver-bearing veins remain only partially tested or have not been drilled;
• Geophysical and geochemical anomalies identify additional target areas for follow-up; and
• The project is a priority silver-focused exploration asset for the Company.

The Company is planning follow-up work, including detailed structural mapping, additional prospecting and rock - soil geochemical sampling, additional geophysical surveys, and additional trenching and diamond drilling, focused on the northwest region of the Keymet Project.

David Martin, P.Geo., (New Brunswick and Newfoundland and Labrador), a Qualified Person as defined by NI 43-101 and VP Exploration for Great Atlantic, approved the technical information contained in this News Release.

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About Great Atlantic Resources Corp.: Great Atlantic Resources Corp. is a Canadian exploration company focused on the discovery and development of mineral assets in the resource-rich and sovereign risk-free realm of Atlantic Canada, one of the number one mining regions of the world. Great Atlantic is currently surging forward building the company utilizing a Project Generation model, with a special focus on the most critical elements on the planet that are prominent in Atlantic Canada, Gold, Copper, Zinc, Nickel, Cobalt, Antimony and Tungsten.

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This press release includes certain statements that may be deemed "forward-looking statements". All statements in this release, other than statements of historical facts, that address future exploration drilling, exploration activities and events or developments that the Company expects, are forward looking statements. Although the Company believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, such statements are not guarantees of future performance and actual results or developments may differ materially from those in forward-looking statements. Factors that could cause actual results to differ materially from those in forward-looking statements include exploitation and exploration successes, continued availability of financing, and general economic, market or business conditions.

Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.

Great Atlantic Resource Corp.
888 Dunsmuir Street - Suite 888, Vancouver, B.C., V6C 3K4

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