Anax Metals (ASX:ANX) has begun a Feasibility Study assessing whether heap leaching could add a second processing stream to its planned Whim Creek copper concentrator in Western Australia.
The study, expected to be completed in the March 2027 quarter, will upgrade the company’s September 2023 Whim Creek heap leach Scoping Study.
Existing permitted heap leach infrastructure could allow Anax to process lower-grade and transitional ore alongside the flotation of higher-grade sulphide material through the proposed concentrator.
The Feasibility Study will incorporate results from 1m column leach test work undertaken with the Commonwealth Scientific and Industrial Research Organisation (CSIRO). The work achieved copper extraction of 77–80% and zinc extraction above 90% from lower-grade ores.
Managing Director Geoff Laing says the heap leach study could broaden the project’s development case without changing Anax’s immediate focus.
“While our immediate focus is advancing the concentrator project to development, with front-end engineering design and financing discussions advancing well, the heap leach opportunity provides upside potential to the compelling base case concentrator project,” Laing says.
“The combination of existing permitted heap leach infrastructure along with larger-scale column test work provides an important platform for this study, which will incorporate enhanced processing strategies, current costs, and metal prices.”
Study builds on concentrator economics
Anax’s February 2026 Definitive Feasibility Study update estimated the standalone concentrator would generate $723 million in pre-tax free cash flow over a 10-year mine life.
The update outlined a pre-tax net present value of $501 million using a 7% discount rate, a 98% internal rate of return, and an all-in development cost of about $91 million.
Those estimates are on a 100% project basis and do not incorporate Anax’s August 2026 update, which increased the Mons Cupri mineral resource estimate by 24% to 6.32 million tonnes @ 1.38% copper equivalent. As reported by Mining.com.au, Anax shares rose 10.81% on 28 August following the resource announcement.
The company notes the heap leach study will examine pyrite leaching, revised copper and zinc recoveries, updated metal prices and exchange rates, and new capital and operating cost estimates.
It will also assess how heap leach production could be integrated into the wider development schedule, alongside potential marketing and offtake arrangements for copper cathode and zinc sulphate crystals.
Meanwhile, Anax is developing its preconcentration and bioleaching technology for use at Whim Creek and potential future commercialisation.
Anax Metals is a minerals explorer and developer focused on copper, zinc, lead, silver, and gold assets. It holds an 80% interest in the Whim Creek Project in the Pilbara region of WA.
Write to France Pinzon at Mining.com.au
Images: Anax Metals
