Troilus Provides Update on Basic and Detailed Engineering Progress with BBA

Press Release

June 10, 2025, Montreal, Quebec – Troilus Gold Corp. (TSX: TLG; OTCQX: CHXMF; FSE: CM5R) (“Troilus” or the “Company”) is pleased to provide an update on the progress of basic and detailed engineering at its copper-gold Troilus Project (the “Project”), led by engineering partner BBA Inc. (“BBA”) based in Montreal, Quebec. Since being awarded the mandate earlier this year (see January 28, 2025 press release), a dedicated team of approximately 45 full-time engineers and specialists has been advancing key workstreams on schedule as the project moves forward on the path to construction readiness.

Highlights of engineering progress to date include:

Process Flowsheet Finalized

• A comprehensive review of the May 2024 Feasibility Study was completed earlier this year.
• Key trade-off studies were conducted, resulting in design improvements to support scalability, operational robustness, and energy efficiency, with minimal impact to CAPEX.
• The optimized main process flowsheet was finalized on schedule, supporting the broader detailed engineering timeline.

12-week Initiation Program Complete

• EPCM contract awarded, and engineering team fully mobilized
• Contracting matrix completed and procurement strategy launched, with multiple RFPs issued
• Finalization of EPCM and owner’s team organizational structures

Justin Reid, CEO of Troilus, commented “We’ve made excellent progress in recent months thanks to the strong collaboration between BBA and our internal project team. Finalizing the flowsheet on schedule marks a major milestone and speaks to the precision and discipline guiding our development approach. BBA’s deep familiarity with the site and its track record on world-class projects like Canadian Malartic and Detour Lake, continues to add significant value. We look forward to sharing further technical developments as we advance toward construction readiness.”

About BBA Inc.

BBA Inc. is a leading Canadian engineering firm with over 45 years of experience in the energy, mining, and natural resources sectors. Known for its strong technical expertise and practical approach, BBA has contributed to major projects like Canadian Malartic and Detour Lake. The firm brings a deep understanding of complex sites and has a long history with the Troilus project, having previously supported flotation circuit optimization under Inmet Mining. With 20+ offices across Canada, the United States, and Chile, BBA supports clients globally with integrated solutions from early studies to execution.

About Troilus Gold Corp.

Troilus Gold Corp. is a Canadian development-stage mining company focused on the systematic advancement of the former gold and copper Troilus Mine towards production. Troilus is located in the tier-one mining jurisdiction of Quebec, Canada, where it holds a large land position of 435 km² in the Frôtet-Evans Greenstone Belt. A Feasibility Study completed in May 2024 supports a large-scale 22-year, 50ktpd open-pit mining operation, positioning it as a cornerstone project in North America.

For more information:

Caroline Arsenault
VP Corporate Communications
+1 (647) 276-0050
info@troilusgold.com

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