💰Gold in the trash? Not quite. But we are rethinking mine waste as a resource. Across the U.S., legacy mining sites have left behind open pits, shafts, and extensive tailings piles. Historically considered waste, these materials might contain critical minerals and other minerals. These minerals are essential to modern technologies—powering everything from smartphones and electric vehicles to medical devices and defense systems. Many occur alongside commodities like gold, zinc, and coal. USGS sc