Canadian copper development company Highland Copper has reported positive results of a preliminary economic assessment (PEA) and mineral resource estimate for its White Pine North Copper project in the US.

The mine is located in the copper range district of the Upper Peninsula of Michigan.

The PEA released by the company provides a base case assessment of mining the mineral resources of the White Pine copper project.

White Pine North is the only project using existing infrastructure to reduce initial capital expenditures, currently valued at $457m.

The project is an extension of the historic White Pine mine, which operated from 1953 to 1995.

Highland Copper said in a statement: “The PEA was prepared in connection with the company’s ongoing strategic review process. The PEA and mineral resource estimate have been prepared by G Mining Services (GMSI).”

The PEA highlighted an after-tax net present value (NPV) of $416m (at 8% discount) and an after-tax internal rate of return (IRR) of 16.8%.

According to the PEA, new resource estimates reveal that the White Pine North project contains an indicated mineral resource of 133.4Mt at 1.07% Cu and 14.9g/t Ag, containing 3.2 billion pounds of copper and 63.8 million ounces (Moz) of silver.

Annual LOM payable copper and silver production is expected to reach 89 million pounds and 1.3 million ounces (Moz) respectively over a 25-year mine life.

Copper mineralisation at the White Pine deposit occurs in two types, one as fine-grained sulphide (chalcocite) and the other as native copper.