Rick Pacheco, precipitation operator at Molycorp Minerals in Mountain Pass, Calif. transfers the didymium from holding tanks to the finishing room during the production of the rare earth elements at the Mountain Pass Mine on August 19, 2009. The open pit mine is home to the world's richest proven reserve of "rare earth" metals, a family of minerals vital to producing the powerful, lightweight magnets used in the engines of Toyota Motor Corp's Prius and generators in wind turbines. The same kind of magnets power the fins that steer precision-guided missiles. To match feature ENVIRONMENT-MINING/TOYOTA
REUTERS/David Becker (UNITED STATES)