Toronto-listed Hudbay Minerals has announced the results of a prefeasibility study (PFS) for Phase 1 of its Copper World project, in Arizona.

Phase 1, which is a standalone operation requiring state and local permits only, will produce 85 000 t/y over 20 years at an average cash and sustaining cash cost of $1.47/lb and $1.81/lb, respectively.

The 20-year mine life is four years longer than the Phase 1 mine that was presented in the preliminary economic assessment (PEA), which was published in 2022.

At a copper price of $3.75/lb, the after-tax net present value of Phase 1, using an 8% discount rate, is $1.1-billion and the internal rate of return is 19%.

The capital cost estimate was lowered from $1.9-billion in the PEA, to $1.3-billion, owing to the deferral of the construction of a concentrator leach facility to year four, with the potential to be fully funded from operating cash flows or benefit from future government incentives for critical minerals processing.

The PFS contemplates a simplified project flow sheet, including a 60 000 t/d sulphide concentrator that will produce copper concentrate as a final product until the addition of a concentrate leach facility and a solvent extraction and electrowinning plant in year five that will allow the project to produce copper cathodes.

The production of copper cathodes will reduce the project’s carbon footprint, make Copper World the third largest domestic copper cathode producer in the US and bolster the country’s green energy independence with “Made in America” copper.

Together with the PFS, Hudbay has updated the mineral resource estimates for the project, which increases the global measured and indicated mineral resources (inclusive of mineral reserves) to 1.2-billion tonnes at 0.42% copper, representing a 4% increase in total in-situ copper. This confirms significant upside at Copper World with an intended Phase 2 expansion of mining activities onto federal land to further enhance the project economics and extend the mine life well beyond 20 years.