Troilus Reports Updated Technical Report Following Completion of Basic Engineering, Delivering After-Tax US$3.2 Billion NPV5%, 22% IRR, and Cashflow of US$6.9 Billion at Base Case Gold Price of US $3,600/oz

Troilus Mining Corp. (TLG) released an updated NI 43-101 Technical Report for its 100%-owned Troilus gold-copper project in Quebec, dated September 8, 2026. The report follows the completion of Basic Engineering, which involved approximately 95,000 engineering hours and C$21.3 million in engineering fees.

At base case long-term prices of US$3,600/oz gold, US$5.00/lb copper, and US$50.00/oz silver, the project demonstrates an after-tax NPV5% of US$3.2 billion, an after-tax IRR of 22%, and an after-tax payback of 3.6 years. Cumulative after-tax cash flow is estimated at approximately US$6.9 billion. Pre-tax metrics include an NPV5% of US$5.3 billion and a pre-tax IRR of 27%.

The updated mine plan outlines an approximately 26-year mine life with a 50,000 tpd nameplate throughput, with potential to increase to 52,000 tpd from Year 3. Life-of-mine payable production is projected at 5.63 moz gold, 472 Mlb copper, and 10.88 moz silver. During the 21-year active mining period, average annual payable production is expected to be 251 koz gold, 20.1 Mlb copper, and 466 koz silver. The life-of-mine strip ratio has improved to 2.4:1, down from 3.1:1 in the 2024 Feasibility Study.

Updated Mineral Reserves total 478 Mt grading 0.44 g/t Au, 0.05% Cu, and 0.92 g/t Ag, containing 6.7 moz Au, 568 Mlb Cu, and 14.2 moz Ag. Reserve tonnage increased approximately 26% versus the 2024 Feasibility Study.

Initial capital is estimated at US$1.428 billion, with an AACE Class 3 accuracy of +15%/-10%. This estimate excludes sunk costs planned through Q1 2027 and includes capitalized operating costs and revenues. Approximately 90% of pricing inputs were validated against current market quotations.

Life-of-mine operating costs are estimated at US$19.21/t mill feed. Life-of-mine cash costs are projected at US$1,297/payable gold ounce, with a life-of-mine AISC of US$1,340/payable gold ounce net of copper and silver credits.

Construction is anticipated to start in 2027, with first ore targeted for September 2029 and commercial production targeted for March 2030. Permitting, financing, procurement, and detailed engineering are all described as advancing in parallel.

Troilus Mining Corp. (TLG) has released an updated Technical Report that advances the project from feasibility-level definition to Basic Engineering completion, achieving AACE Class 3 capital accuracy. This update represents a significant project-level milestone rather than a routine drill result.

Key improvements compared to the May 2024 Feasibility Study include an extension of mine life from 22 years to approximately 26 years and a 26% increase in reserve tonnage. The strip ratio has improved from 3.1:1 to 2.4:1, and life-of-mine payable copper production is projected to increase by approximately 21%. Additionally, gold doré production is now planned from initial start-up rather than being deferred.

The report calculates an after-tax net present value (NPV) of US$3.2 billion. This figure compares with the company’s approximate market capitalization of C$1.29 billion, or about US$0.94 billion at the report’s assumed exchange rate of US$1.37/C$. It is important to note that this NPV is a long-term, discounted project-level figure dependent heavily on commodity prices, rather than a current asset value.

The base case assumes a gold price of US$3,600/oz, with economics showing high sensitivity to gold prices. Sensitivity analysis indicates the following outcomes: - At US$2,000/oz: after-tax NPV falls to US$384 million, with an internal rate of return (IRR) of 7.4% - At US$2,500/oz: NPV is US$1.322 billion, with an IRR of 12.8% - At US$3,000/oz: NPV is US$2.190 billion, with an IRR of 17.2%

The initial capital requirement of US$1.428 billion is substantial relative to the company’s current cash position and market capitalization. Financing has not yet been closed. While a US$1.2 billion debt mandate is in place, it remains subject to due diligence, credit approvals, and conditions precedent. The provided materials do not include the initial capital figure from the prior 2024 Feasibility Study, so the exact change in capital expenditure versus the prior study cannot be quantified.

This update serves as a higher-confidence study reflecting material project de-risking, but it does not constitute a financing close, construction approval, or first production.

Troilus Mining Corp. (TSX: TLG, OTCQX: CHXMF, FSE: CM5) is a Canadian development-stage mining company whose flagship asset is the Troilus gold-copper project in north-central Quebec. Located within the Frôtet-Evans Greenstone Belt, the project encompasses a land position of approximately 435 km². It is a past-producing mine site that yielded more than 2 million ounces of gold and approximately 70,000 tonnes of copper between 1996 and 2010.

An updated 2026 Technical Report outlines a conventional open-pit operation processing 50,000 tpd from the 87, J, X22 and SW deposits. The facility will produce gold-silver doré and gold-rich copper concentrate. Existing infrastructure includes road access, a 137 km 161 kV transmission line, and previously mined pits. Additionally, a 70 MW hydroelectric power allocation from Hydro-Québec was secured in June 2026. The project is being advanced under an integrated EPCM structure with BBA leading engineering and procurement and EBC providing construction management services.