The AIM-traded company said the study estimated an after-tax NPV of $660.3m and IRR of 59.6% at its base-case tungsten price, with after-tax free cash flow of $1.06bn over an initial eight-year mine life and payback in one year.

At the 12 June spot price, the project’s after-tax NPV rose to $1.37bn, with an IRR of 101.6% and payback of six months.

Pilot Mountain is expected to produce 15,916 tonnes of WO3 from probable reserves of 20,275 tonnes, with initial capital expenditure estimated at $288.7m.

Chief executive Oliver Friesen said the project was positioned as a “unique opportunity” for near-term US tungsten production, with first production targeted for the fourth quarter of 2028.

At 1145 BST, shares in Guardian Metal Resources were down 10.45% at 197p.

Reporting by Josh White for Sharecast.com.

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