Mine tailings are often abandoned as they contain low-grade ore or retain hazardous substances from processing, but they still hold considerable value that is being unlocked in Queensland.
It is estimated that tailings also comprise between 5% and 15% of the metals and minerals they were originally mined for. Simultaneously, the world is transitioning from fossil fuels to renewable energy. However, the supply of metals and minerals necessary for energy transition technologies cannot keep pace with demand.
Within Queensland, Australia, there are historic and newly produced tailings due to the established and globally respected mining industry. The sector is turning to mine waste as an alternative source of critical minerals and materials, in line with corporate environmental, social, and governance (ESG) standards.
The potential value in Queensland’s tailings is considerable, with cobalt potentially worth hundreds of millions of dollars. With successful tailing extraction projects already completed, many others are in the exploratory stage, assisted by regulatory and funding support from the state government.
Projects and innovation are receiving support from the Queensland Government, which is laying the groundwork for transparency and traceability throughout mineral supply chains.
Challenges with supplies of cobalt and rare earth elements
Demand for cobalt could triple by 2030. The mineral is a crucial element in rechargeable lithium-ion batteries. Strikingly, global cobalt production is expected to have a compound annual growth rate (CAGR) of just 1% between 2023 and 2030, according to GlobalData’s forecasts.
A similar supply gap exists with rare earth elements (REEs) such as lanthanum and cerium, which are used in batteries and catalytic converters. However, global supplies are increasingly limited. As much as 97% of global REE supplies are from China, which is reducing exports. China also dominates the production of tungsten and is limiting exports. The metal is pivotal to the energy transition as it is used to improve the efficiency of solar photovoltaic (PV) cells.
With the supply of critical minerals from primary sources restricted, mining companies are turning to tailings. Using such a secondary source can reduce waste, keep existing resources in circulation, remove the environmental impact of new mining, and perform strongly for ESG credentials.
Critical mineral extraction projects in Queensland
Recovering value from tailings is an area of strategic focus in Queensland. Australian company EQ Resources was awarded an exploration permit for minerals (EPM) in June 2024 to begin drilling and sampling with the aim of unlocking tungsten at a site that includes the former Wolfram Camp and Bamford Hill mines.
“Having successfully navigated the permitting process, we are excited to get boots on the ground,” says Kevin MacNeill, Chief Technical Officer at EQ Resources. “Our team of experienced professionals will apply modern exploration techniques and state-of-the-art technologies to maximise Wolfram Camp and the surrounding site’s potential while minimising its environmental footprint.”
MacNeill underlines the way in which EQ Resources is supporting the minerals strategy by reviving a formerly defunct resource. “By leveraging advanced ore sorting and geometallurgical techniques, we’re breathing new life into this historic asset while supporting Queensland’s critical minerals strategy,” he says.
EQ Resources has a track record of revitalising former mines, having already processed two million tonnes of historic tailings in Phase 1 of its Mount Carbine Tungsten Project, which is now Australia’s largest tungsten mine.
The process involved crushing the mine waste then separating it by size. Material over 40mm was designated for quarry sale, while the tailings under 40mm were crushed again and treated with X-ray transmission. Particles less than 6mm were formed into a slurry, then placed in high-capacity gravity separation tables. The entire crushing, screening, and sorting process had an overall tungsten recovery rate of 79.5%.
The resulting high-quality tungsten concentrate is destined for use in battery technologies and energy storage, as well as defence applications. Recovery rates from tailings for other critical minerals can range from 96% for lithium and 61% for copper.
Several other mining companies are actively or intend to undertake mineral extraction to obtain vanadium, REEs, cobalt, copper, and zinc, with all actively supported by the Queensland Government.
Before assessing the development potential of a site, mining companies obtain an exploration permit for minerals (EPM) and where required a mineral development licence (MDL). These are issued by the Queensland Government, which has reduced the cost of EPM rent to zero until 2028.
The uranium tailings of the Mary Kathleen mine in Queensland are among the top 25 highest-grade rare earth mineralisation deposits. They contain an estimated seven million tonnes of grade 3% REEs, predominantly lanthanum and cerium. Studies determine the resource potential of the REEs in these tailings could generate revenue of more than $150m.
Cobalt Blue has successfully reprocessed sulphide-rich mine tailings in Queensland. The company has signed a collaboration agreement with the City Council of Mount Isa to assess the feasibility of re-processing tailings from the Mount Isa copper mine. It is estimated that there are at least ten kilotons of cobalt in Queensland’s copper tailings produced per annum, with a projected worth of A$800m.
“Queensland is sitting on a significant resource of cobalt, copper, and gold,” says Joe Kaderavek, Deputy Chairman of Cobalt Blue. “Recycling that cobalt is great news for both Queensland and global battery sectors.”
International companies are turning to Queensland to harness the supportive legislation and untapped resources. For example, South African mining company Sibanye Stillwater is extracting zinc from the historic tailings of the New Century mine. Although zinc is not listed as a critical mineral in Australia, it is designated as one of five strategic materials, and tailings offer an accessible resource.
Transparency in the critical mineral supply chain
Reusing tailings aligns with all aspects of ESG. Verifying the original source of materials can ensure the supply chain is transparent, ethical, and more sustainable.
Complex transnational supply chains of critical minerals can cover up unethical production practices. Reports of human rights breaches have led to calls for trade sanctions on products from the Democratic Republic of Congo, even though the nation supplies 70% of the world’s cobalt.
The Queensland Government places a high importance on transparency in the supply chain of critical minerals and commissioned a report to map the current landscape of mineral traceability. Though in the early stages of maturity, Queensland is establishing aligned definitions of compliance requirements, identifying critical minerals as commodities within the federal Guarantee of Origin scheme. This is a voluntary framework for emissions accounting and designing data architecture to share product insights with all parties in the supply chain.
Additionally, a research alliance is exploring the disclosure requirements for tailings information. The alliance includes the University of Queensland and multinational mining corporations Anglo American and Newcrest Mining.
Both corporations have committed to the standards of the Global Industry Standard on Tailings Management (GISTM). Principle 15 is to publicly disclose and provide access to information about tailings facilities to support accountability.
Investment in Queensland for critical mineral extraction and processing
The Queensland Government’s support for this vital area of mining and processing is comprehensive, extending beyond ESG and traceability frameworks.
Along with financial support, the Queensland Government is investing in common user infrastructure that will facilitate innovation in Townsville, with the surrounding area rich in copper and zinc refining. The state-owned Queensland Resources Common User Facility will assess the potential of waste streams and other related activities.
Furthermore, the Sustainable Minerals Institute of the University of Queensland facilitates research on extraction from tailings and collaborates with industry. The institute was established with a grant from the Queensland Government in 2001.
The extraction of critical minerals from tailings presents a vital opportunity for mining companies operating in Queensland to increase the supply of high-value critical minerals and materials. Queensland has everything in place to optimise the untapped value from tailings to benefit domestic and international supply chains.
To learn more about the latest critical minerals opportunities available in Queensland, download the Critical Minerals Prospectus below.
