A new study reveals the US is discarding critical minerals like cobalt, germanium, and rare earths in mine waste. Recovering even 1% could eliminate imports, power EVs, defense tech, and cut environmental damage.
Every year, the United States imports huge amounts of critical minerals—elements essential for clean energy, national defense, and cutting-edge technology. But what if the country already mined all the cobalt, germanium, lithium, and rare earths it needed?
A new analysis published in Science suggests exactly that. The catch: almost all of these minerals are being discarded as waste, trapped in mine tailings instead of being recovered and reused.
“These minerals, such as cobalt, lithium, gallium and rare earth elements like neodymium and yttrium, are currently being discarded as tailings of other mineral streams like gold and zinc,” explained Elizabeth Holley, associate professor of mining engineering at Colorado School of Mines and lead author of the study.
From Gold to Waste Piles: The Recovery Challenge
At first glance, the situation seems almost absurd. The United States mines vast quantities of valuable byproducts but allows them to slip through the cracks. The problem, Holley said, isn’t availability—it’s the difficulty of separating tiny amounts of critical minerals from much larger streams of material.
“The challenge lies in recovery,” Holley said. “It’s like getting salt out of bread dough—we need to do a lot more research, development and policy to make the recovery of these critical minerals economically feasible.”
Right now, these valuable minerals often end up in tailings piles—massive waste mounds that must be carefully managed to prevent environmental contamination.
Mapping America’s Critical Mineral Potential
To get a clearer picture, Holley and her team built a detailed database of annual production at federally permitted US metal mines. By pairing this information with geochemical data from the US Geological Survey, Geoscience Australia, and the Geological Survey of Canada, they were able to estimate the quantities of critical minerals being mined but not recovered.
What they found was astonishing: except for platinum and palladium, America already mines enough of the other 70 elements considered critical for modern life—from cell phones and satellites to renewable energy infrastructure and fighter jets.
“This is a brand-new view of ‘low hanging fruit’—we show where each critical mineral exists and the sites at which even 1 percent recovery of a particular critical mineral could make a huge difference, in many cases dramatically reducing or even eliminating the need to import that mineral,” Holley said.
Two Case Studies: Cobalt and Germanium
Some of the findings highlight just how much untapped potential lies in mine waste:
- Cobalt (Co): This lustrous bluish-gray metal is a cornerstone of electric car batteries. It’s already being mined as a byproduct of nickel and copper. According to Holley’s team, recovering less than 10 percent of cobalt currently lost in tailings would be enough to fuel the entire U.S. battery market.
- Germanium (Ge): Known for its use in electronics and infrared optics—crucial for missile sensors and defense satellites—germanium is present in zinc and molybdenum mines. Recovering less than 1 percent of what is currently wasted would cover all U.S. industry needs, wiping out the need for imports.
More Than Economics: The Environmental Argument
Recovering these minerals isn’t just about reducing dependence on foreign supply chains. It’s also about reducing waste and improving sustainability.
“The benefits of enhanced recovery are not only economic and geopolitical but also environmental,” Holley said. “Recovering these critical minerals instead of sending them to tailings piles would reduce the environmental impact of mine waste and open more opportunities for reuse in construction and other industries.”
What Needs to Happen Next
The analysis identifies where the “low-hanging fruit” lies, but the next step is putting that knowledge into action. That means investing in technology to extract elements more efficiently and creating policies that give mine operators incentives to recover them.
“Now that we know which sites are low-hanging fruit, we need to conduct detailed analyses of the minerals in which these chemical elements reside and then test the technologies suitable for recovery of those elements from those specific minerals,” Holley said.
She added that the economics won’t always stack up on their own.
“Although these elements are needed, their market value may not be sufficient to motivate operators to invest in new equipment and processes without the right policies in place.”
A National Opportunity Hidden in Waste
The findings flip the script on America’s reliance on foreign suppliers for critical minerals. With the right mix of science, innovation, and political will, the US could transform waste piles into a strategic resource, powering everything from electric cars to defense satellites—while also reducing the environmental burden of mining.
For now, the cobalt, germanium, and rare earths that could shape America’s technological and energy future are sitting in mine tailings, waiting for someone to see their value.