Mr. Fausto Di Trapani reports

TIERNAN GOLD PROVIDES UPDATE ON FLAGSHIP VOLCAN PROJECT

Tiernan Gold Corp. has provided a project update on its flagship Volcan gold project in Chile's renowned Maricunga gold belt. This update marks a clear shift into an engineering-led, execution-focused phase following the successful completion of the company's reverse takeover (RTO) and TSX Venture Exchange listing. All amounts herein are reported in United States dollars unless otherwise specified.

Highlights

• A total of $53-million provides fully financed technical runway to complete advanced engineering studies and support the submission of a robust environmental impact study (EIS).
• Large-scale, Tier 1 asset with 9.8 Moz (million ounces) measured and indicated gold resources and clear, long-life, district-scale potential.
• Engineering-first strategy focused on derisking and value creation.
• Major technical workstreams under way across geology, metallurgy, engineering and permitting.
• Improving political and regulatory backdrop in Chile, with a more investment-supportive policy direction emerging and a stated focus on accelerating permitting for large, high-quality projects.
• Catalyst-rich outlook through 2026 and 2027 as Volcan advances toward development readiness.

"Volcan is a genuinely exceptional asset; large scale, long life and located in one of the world's most important gold belts," said Fausto Di Trapani, president and chief executive officer of Tiernan Gold. "Since the completion of the RTO, our focus has been clear and deliberate: reduce uncertainty, strengthen the engineering backbone of the project and advance Volcan in a way that creates durable, long-term value for all stakeholders. This is about building confidence technically, operationally and strategically, and doing the hard work now so the project can move forward on solid ground."

Volcan: a large-scale gold development asset

Volcan is one of the largest undeveloped gold projects in Chile, with a measured resource of 124 million tonnes (mt) grading 0.7 gram per tonne gold, an indicated resource of 339 mt grading 0.6 g/t Au for a total of 9.8 million ounces of gold, and an additional inferred resource of 75 mt grading 0.5 g/t for a total of 1.2 million ounces of gold, all located within the Dorado sector of the project.

A preliminary economic assessment (PEA) completed in July, 2025, to which Ausenco Chile Ltd. contributed technical information, highlighted the project's scale and outlined a large-throughput heap-leach operation producing approximately 330,000 ounces of gold per year over the first 10 years of operations delivering strong indicative economics (all-in sustaining costs of under $1,100 per ounce delivering an NPV (net present value) 5 per cent of $1.5-billion at $2,400/oz gold at an internal rate of return of 29 per cent based on assumptions outlined in that study).

While these metrics continue to demonstrate Volcan's size and strategic relevance, Tiernan's focus has now shifted decisively toward strengthening the engineering and technical foundations required to responsibly advance the project through permitting and toward project execution.

Building the right engineering foundation

Since listing publicly, Tiernan has moved quickly to assemble the technical depth, organizational capability and financial flexibility required to advance Volcan in a disciplined and value-driven manner.

Rather than emphasizing the completion of studies for market optics, the company is prioritizing:

• Quality engineering;
• Design optionality;
• Early identification and mitigation of project risks.

This approach is intended to support a high-quality EIS (environmental impact statement), backed by credible engineering and defensible assumptions. Tiernan has partnered with a number of highly regarded consultants with significant Latin American experience including Motherlode Consulting (geology and resource modelling), Turnstone Metallurgical Services (metallurgy), SGS (metallurgical testwork) and Ausenco (engineering, permitting and study support), as the company advances Volcan into its next phase of development.

Geology and resource: unlocking a better understanding

A comprehensive geological reinterpretation program is under way at the Dorado deposit, aimed at further improving understanding of mineralization controls and informing future mine and process design.

Key elements include:

• Systematic relogging of historical drill core;
• High-resolution core photography;
• Terraspec hyperspectral analysis of core and pulp samples;
• Development of geologically driven domains incorporating structure, lithology and alteration; moving beyond simplified grade-shell constraints.

This work is foundational in nature, designed to enhance geological understanding and support downstream engineering decisions. While no outcomes are implied, Tiernan believes this approach is critical to responsibly unlocking Volcan's full potential.

Metallurgy: delivering value

Tiernan has initiated a phased metallurgical program designed to deepen process understanding and optimize flowsheet design for Volcan as the project advances. This work builds on prior test programs and applies modern analytical methods and broader sample coverage to further strengthen design inputs and value outcomes.

Current work is designed to evaluate:

• Gold and copper deportment;
• Cyanide consumption dynamics;
• Heap-leach kinetics across a representative grade range;
• Comminution and crushing options, including HPGR versus conventional crushing.

Importantly, nothing is off the table. While SART and HPGR may offer recovery and cyanide consumption benefits, they also introduce material capital and operating costs. The company's objective is to identify the configuration that maximizes overall project value.

Permitting, water and ESG (environmental, social and governance): advancing with intent

With permits in hand, Tiernan is on the cusp of commencing initial environmental baseline characterization work, including early meteorological station deployment. These activities form the foundation of a comprehensive EIS submission.

Water remains a strategic focus. Volcan benefits from existing permitted water rights, which the company views as a material competitive advantage. In parallel, Tiernan is actively monitoring rapidly advancing desalination initiatives in northern Chile, including emerging public-private partnership models which could support long-term water security for large-scale mining projects in the region.

Community engagement: moving forward the right way

In parallel with technical and permitting activities, Tiernan continues to advance early, structured engagement with local communities and regional stakeholders in the project area. The company views meaningful, transparent engagement as a foundational element of responsible project development and a critical input into the EIS process. As technical work progresses, community engagement will continue to be integrated into project planning to ensure that development pathways are informed, responsible and aligned with regional priorities.

Looking ahead: a high-impact phase for Volcan

With funding secured, a strengthened technical team in place and a clear execution mandate, Tiernan is entering what it expects to be a high-impact period of stakeholder value creation for Volcan through 2026 and 2027.

Future updates will provide regular, substantive progress reports as the company advances geology, metallurgy, engineering and permitting in parallel -- setting Volcan up to move forward from a position of strength.

Qualified person statement

The scientific and technical information contained in this news release has been prepared by Sergio Lagos, RM CMC, who is an independent qualified person as defined under NI 43-101.

About Tiernan Gold Corp.

Tiernan Gold is focused on the disciplined derisking of the Volcan gold project strategically located in the Atacama region of Chile, on the Maricunga gold belt, a jurisdiction that has a long-established history of mining with a number of operating mines, new mines under construction and major projects being developed.

We seek Safe Harbor.