Tailings Could Meet Most US Critical Mineral Needs as List Expands

A new scientific analysis and a parallel federal push to expand the United States list of critical minerals are prompting renewed focus on an underused domestic resource: the metals sitting in mine waste. Researchers say recovering small fractions of byproduct elements locked in tailings and other mining streams could meet most U.S. needs for critical minerals, while a draft federal list aims to steer policy and investment toward boosting domestic supply and insulating industries from foreign disruptions.

The analysis, published in Science and led by Elizabeth Holley of the Colorado School of Mines, combined production records from federally permitted metal mines with geochemical data from national surveys to assess the content of already excavated rock. Holley and colleagues examined more than 26,000 ore samples and 70 elements, and concluded that nearly all the critical minerals required annually for U.S. manufacturing are present in domestic mining streams but are not being captured. Of those elements, the team said targeted recovery could eliminate most imports except platinum and palladium.

The study highlighted specific opportunities. Recovering less than 10 percent of...