Full-value Copper Mining: A Gateway to Critical Mineral Resources

S. Duyvesteyn, D. Wellman, K. Jenkins, C. Eyzaguirre, C. Smith
Rio Tinto,
United States

Keywords: processing, copper mining, supply chain


Stability and sufficiency of domestic production of essential, foundational materials has received bipartisan recognition as a primary risk in securing the nation’s transition to clean energy, security and economic prosperity. For nearly two decades, it has been consistently noted that interruption of strategic and critical mineral supplies would afford one of the greatest disruptions to U.S. industry. As highlighted by IEA (2022) addressing this risk requires establishing diversified sources of new supply, innovation across the value chain, recycling, market transparency, enhancing environmental, social and governance standards, and increasing international collaboration across allies. Although not currently on the U.S. critical mineral listing, copper is an essential strategic mineral in the transition to clean energy and maintaining energy and national security. The global transition to green energy and a low-carbon future alone has been projected to increase the demand for copper from 12 – 213% through 2050 (World Bank Group, 2020). Additionally, full-value copper mining provides a gateway to the production of numerous critical minerals that are, currently, dominantly produced in adversarial countries. Innovation across the copper value chain is enabling Rio Tinto to unlock new resources of key critical minerals, as well as enhance production of strategically important minerals, namely, copper. For example, at low parts per billion concentrations, tellurium was once thought to be of such insignificance in the Bingham Canyon ore body that it passed through the copper value stream to tailings. However, approximately 90% of the world’s tellurium resource is contained in copper ore and the transition to clean energy is increasing demand at approximately 5.5% per annum. It is inherent upon resource owners to responsibly assist in addressing this growing national need. Through innovation and implementation of new processes, Rio Tinto has established one of only two domestic value streams for the production of approximately 20 tons of tellurium per annum, essential to the manufacturing of ultra-high purity semiconductor materials and thin film photovoltaic solar panels. Innovation in technology, as well as how we have traditionally look at mine resources, are opening essential advancements necessary to secure the critical mineral domestic supply chain. What was once viewed as waste or by-product streams are now becoming key national resources. Through partnerships with the U.S. Department of Energy’s Critical Materials Institute (CMI), national laboratories, universities, and other industry partners, Rio Tinto is unlocking new socially responsible and economically viable gateways to critical minerals such as palladium, platinum, indium, germanium, gallium, and others. Herein we will present an overview of work in the development of these value streams from technological innovation to implementation.