Sirios Discovers High-Potential Gold Halo in Western Sector of Aquilon Project in Eeyou Istchee James Bay, Quebec

On December 4, 2025, Sirios Resources announced assay results from its summer diamond drilling campaign on the Aquilon Gold Project in Quebec. The 13-hole, 5,420-metre program, funded by partner Sumitomo Metal Mining Canada, led to the discovery of a large, anomalous gold halo in the previously unexplored western sector of the project.

Key findings include: - The gold halo extends over 1 km in length, is several hundred metres wide, and remains open in all directions. - The weighted average grade across the entire mineralized halo is 0.26 g/t Au. - Highlight intercepts include hole AQ25-119, which returned 2.55 g/t Au over 4.8 metres, including a higher-grade section of 5.51 g/t Au over 1.0 metre. Other intercepts were more modest, such as 1.12 g/t Au over 4.0 metres in hole AQ25-118. - With the completion of this program, Sumitomo's spending commitment has exceeded $4.8 million, entitling it to earn a 51% interest in the Aquilon project, forming a joint venture.

The discovery of a large, new gold system at Aquilon is a material positive for Sirios.

Sirios Resources is a junior exploration company focused on gold projects in Quebec's Eeyou Istchee James Bay territory. - Flagship Project: The 100%-owned Cheechoo gold project is the company's main asset, located adjacent to the Éléonore gold mine. A major milestone was the updated MRE filed in August 2025, which showed a significant increase in both ounces and grade from the 2022 estimate. - 2025 MRE: 1.3 Moz Indicated at 1.12 g/t Au and 1.7 Moz Inferred at 1.23 g/t Au. Crucially, this update introduced a higher-grade, stope-constrained underground resource of 446,000 ounces at 3.09 g/t Au (Inferred). - Secondary Project: The Aquilon project, also in James Bay, is now a 49/51 joint venture with Sumitomo Metal Mining Canada. It is a high-grade, early-stage exploration project where the latest news has defined a new, large gold system.