Molycorp Inc., the only U.S. producer of rare earths, intends to mothball its mine in California, laying off almost 500 workers and suspending the country’s sole source of the 15 elements used in magnets, batteries and other high-tech products.
The company said Wednesday that it would put its Mountain Pass mine on the California-Nevada border on “care and maintenance” by Oct. 20, although it would continue to produce at processing…
