PERTH (miningweekly.com) – A restart study for the Nifty copper project, in Western Australia, has estimated that it would require a capital injection of A$149-million, and could produce 25 000 t/y of copper cathode.

The restart is focused around the first phase of heap leach retreat and oxide openpit, and it is envisaged that the life will extend to the sulphide stage of the openpit with a considerably larger resource available.

The sulphide study has already commenced with design optimisation and metallurgical testwork currently being undertaken.

ASX-listed Cyprium Metals on Friday told shareholders that based on the current copper price of $4.60/lb, the Nifty operation was projected to have a net present value of $277-million and an internal rate of return of 37%, with C1 costs estimated at $1.91/lb.

Oxide cathode production would reach 146 100 t of metal, with the oxide mine life estimated at just over six years, between 2023 and 2029, with a sulphide potential of more than 20 years.

“We are very pleased to announce the results of the Nifty copper project restart study. The fundamentals of the project are robust, which excludes the addition of an updated mineral resource estimate to be completed in the coming months and the conversion of inferred resources during the pit mining,” said Cyprium MD Barry Cahill.

“Metallurgical optimisation continues to have success with our heap leach metallurgy knowledge clearly showing an improved treatment path for the oxide material considering over 200 000 t of copper metal cathode has already been extracted and produced using a heap leach process on this site.”

The Nifty operation has produced more than 700 000 t of copper metal between commencement of the oxide operation in 1993 and November 2019, when the mine was placed into care and maintenance. The single deposit is still ranked in the top twenty copper mineral resources by in-situ copper metal tonnes in Australia, with considerable potential to increase this further.

“A great effort by the team to get this study completed within a year of acquiring the project. We now look forward to getting the finance completed and accelerating construction to plating copper metal by the second half of next year,” said Cahill.

Cyprium is hoping to finalise financing for the project during the second quarter of this year.