A new study from the Colorado School of Mines has found that the United States could meet much of its demand for critical minerals by recovering materials currently discarded in mining waste.
Published this week in Science, the analysis shows that nearly all critical minerals used in clean energy technologies, electronics, and defense applications are already present in ore processed at US mines. However, the majority of these materials end up in tailings and other waste streams rather than being refined for use.
The analysis highlights cobalt and germanium as prime examples. Recovering less than 10% of the cobalt already mined and processed but lost to waste streams would be sufficient to supply the entire US battery market, the authors assert. For germanium, reclaiming under 1% from existing zinc and molybdenum operations would eliminate the need for imports altogether.
The study examined 70 elements across US mining operations. Aside from platinum and palladium, the researchers found that all could theoretically be sourced domestically with improved recovery methods.
Elizabeth Holley, associate professor of mining engineering at Colorado School of Mines and lead author of the study, described mine tailings as a significant untapped resource. “We’re already mining these materials,” she said.
“The question is whether we capture them or throw them away.”
The team combined production data from federally permitted US mines with ore concentration data from the US Geological Survey and other international sources to estimate the amount of critical minerals lost in waste streams.
The findings highlight both a strategic opportunity and a challenge. While recovering minerals from tailings could reduce US dependence on foreign sources and lower the environmental footprint of mining, the researchers note that current market conditions often make byproduct recovery uneconomic. They suggest that additional research, development, and policy incentives will be needed to make large-scale recovery viable.
The study comes as the Trump administration is seeking to secure supplies of critical minerals needed for the energy transition, amid concerns about China’s dominant position in mineral production and processing.
Tailings could meet much of US critical mineral demand – study