Australian Mining

Cyprium Metals has begun acid leaching at its Nifty copper complex for the first time since 2009, marking a significant restart milestone as first copper cathode production shifts to the December 2026 quarter.

The Western Australian operation’s existing heaps are being commissioned with acid solution, while refurbishment of the solvent extraction and electrowinning (SX-EW) plant approaches completion.

First cathode is now expected during fourth-quarter wet commissioning and ramp-up, following plant energisation.  In July, Cyprium was targeting first production in the September quarter, with construction nearing practical completion and attention turning to operational readiness.

Cyprium executive chairman Matt Fifield said the company was completing the first phase of its phased restart in WA’s Paterson region.

“We are now completing our Phase 1 project which will produce copper from our existing heaps and cathode from the B Train of our SX-EW plant,” he said.

The start of acid leaching follows a successful trial of direct injection technology, which demonstrated that Nifty’s existing heaps could accept injected solution at commercial flow rates of approximately 250 cubic metres per hour and beyond.

The 14-well trial used water without added acid and generated copper-bearing solution in sufficient grade and quantity to commission the SX-EW plant.

“We are commissioning our heaps, ponds and acid circuit now. Applying acid solution to the existing heaps is a significant milestone for Cyprium – this is the first leach on these pads in nearly twenty years,” Fifield said.

“We have already filled the ponds with enough copper-rich solution to support the plant startup. Now we expect to start quickly building grade to support production.”

Cyprium has since expanded the wellfield to 98 production wells, providing access to approximately 1.7 million tonnes of material for future leaching. Additional wells will be installed progressively to support production plans.

Both the solvent extraction and electrowinning areas are substantially mechanically complete. Remaining work includes installing cell top furniture, loading cathodes and anodes, refurbishing the stripping machine and completing electrical and instrumentation activities.

Testing identified failures in existing high-voltage components, requiring replacement parts. Cyprium has progressed pre-commissioning activities using auxiliary power while completing the electrical work needed for safe energisation.

All regulatory approvals supporting the Phase 1 restart are in place, pending successful commissioning, and construction has recorded zero lost time injuries.

“In the plant, we are rapidly closing out scopes of work and focused on delivering a safe and successful commissioning and start-up,” Fifield said.

Beyond the restart, Cyprium is completing planning and capital estimates for a potential increase in SX-EW cathode production capacity from approximately 6000 tonnes per annum to 20,000 tonnes per annum.

The expansion would depend on generating additional copper in leach from existing heaps, surface stockpiles and open-pit oxide material. Cyprium also expects to report updated Nifty mineral resource and ore reserve estimates in the second half of 2026.

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