With copper prices near record levels at around US$14,400 ($20,220) per tonne, the red metal can provide a valuable anchor for companies chasing the higher-value but more complicated rainbow of rare earth elements (REEs).
A discovery of the strategic metal alongside REEs can potentially improve project or mine economics and give investors greater confidence to back a development.
One example is the Olympic Dam mine in South Australia, where copper is supporting cash flow for BHP Group (ASX:BHP) as the company finally evaluates its multibillion-dollar rare earth potential.
At the junior explorer level, Thor Energy’s (ASX:THR) Alford projects on South Australia’s Yorke Peninsula are being advanced around low-cost copper recovery, enhancing the potential viability of developing its magnet and heavy rare earths exposure.
Meanwhile, New Frontier Minerals (ASX:NFM) is earmarking near-term cash generated from its NWQ Copper Project’s Big One deposit to advance a high-potential critical minerals and rare earths portfolio without having to rely entirely on capital markets.
Red metal joins hot REEs
In its latest results, RareX (ASX:REE) has potentially added copper to its own critical minerals mix after identifying a 74m zone of anomalous copper sulphide mineralisation in drilling at its Niobe prospect in the Khaleesi Project, Western Australia.
Niobe is the largest and most advanced target at the project, which sits within the Khaleesi Alkaline Intrusive Complex in the East Yilgarn region of WA.
One hole returned a peak portable X-ray fluorescence (pXRF) reading of 5,724 parts per million (ppm) copper (0.57%), with numerous readings above 1,500ppm and elevated copper sustained across much of the 77–151m downhole interval.
Managing Director and CEO James Durrant says the identification of the copper mineralisation is an exciting new discovery alongside the broader gallium, niobium, and rare earth opportunity RareX is evaluating at Niobe.
“[The discovery] adds another dimension to what is emerging as a highly prospective and geologically complex system at the Khaleesi Alkaline Intrusive Complex,” Durrant says.
“The pXRF results are preliminary and we are awaiting laboratory assays, however the scale and consistency of the copper anomalism across [drill hole] KRC012 warrants follow-up and alteration vectors suggest the hotter part of the system is yet to be found.
“We are integrating KRC012 into the broader program interpretation and we are excited to be part of a newly discovered mineralised system in the Albany-Fraser [orogen].”
The assay results are expected in the next four to six weeks as RareX’s drilling continues.
Historical exploration in that part of the prolific Yilgarn Craton by major companies, including AngloGold Ashanti (NYSE:AU), IGO (ASX:IGO), and Fortescue (ASX:FMG), largely drilled through the younger cover and stopped once basement was reached. That leaves much of the underlying intrusive complex in the remote east of WA effectively untested.
Early success
The result comes just weeks after RareX kicked off its 3,500m maiden reverse circulation drilling campaign at Khaleesi, testing five priority targets across the district-scale alkaline intrusive complex.
Encouragingly, Niobe sits beneath a roughly 5km by 3km surface gallium anomaly and coincident magnetic and gravity features.
Hunt for high-demand minerals
Like many critical minerals, gallium is an essential, non-substitutable material for defence and other key industries. Its uses span advanced electronics, weapon systems, satellites, and solar technology, as well as semiconductors and data-centre hardware.
With China controlling almost all global gallium production and tightening export controls, Western nations, especially the US, are increasingly focused on securing alternative sources.
As with other critical minerals, quoted gallium prices can vary significantly, from Chinese material at around US$400 per kilogram to some European market sources publishing prices in the thousands of dollars per kilogram. While the market is not as straightforward as some others, the variance illustrates the potential premium attached to secure non-Chinese supply.
Similarly, global niobium supply is heavily concentrated, with three mines accounting for most production — two in Brazil with Chinese involvement and a smaller operation in Canada.
The bulk of niobium is used to strengthen steel while reducing its weight, making it important for construction, transport, and infrastructure. But demand is also emerging from higher-tech applications including superconductors, next-generation batteries, aerospace, and medical imaging.
The current spot price for ferroniobium is quoted at US$40–70 per kilogram, while the higher-purity niobium pentoxide trades around US$45–60 per kilogram.
Broad vision
Beyond Khaleesi, RareX is focused on advancing the metallurgy of its Cummins Range Project in WA, which contains magnet-grade rare earths, battery-grade phosphate, and significant gallium and scandium.
The company has exposure to other critical minerals through its consortium with Iluka Resources (ASX:ILU), which is pursuing the Mrima Hill Rare Earths Project in Kenya. RareX also holds material investments in Kincora Copper (ASX:KCC), Cosmos Exploration (ASX:C1X), and Canada Rare Earth (TSXV:LLV).
Write to Christina Wagstaff at Mining.com.au
Main image: Unsplash
