Civilization as we know it wouldn’t exist without rare earth elements. No smartphones, LEDs, wind turbines, or even car batteries. REEs, such as cerium and scandium, are scattered throughout the earth’s crust. e DOE recently funded a wave of research to boost U.S. REE production to cope with demand, which is rising about 5 percent every year. Each step of coal production—mining, cleaning, and burning—creates REE-enriched material. The goal is to use that waste, now sitting in landfills and storage ponds, in a way that’s cheap and environmentally friendly. The challenge now is extracting the metals, says Sarma Pisupati, a professor of energy and mineral engineering at Pennsylvania State University. His research focuses on rinsing raw shale with an ammonium-sulfate solvent to collect REEs early in the coal-production process.