A Cleaned-Up Gold Rush

For all its eternal glitter, gold is not lustrous to mine. Modern prospectors use bulldozers and giant stone crushers, processing seven tons of ore to recover a single ounce of gold. Stimulated by high prices, mining intensified in the late 1970s and has now reached boom stages.

The gold miners, though, have run into strong opposition from environmentalists, especially in California's storied motherlode country near Sonora and in the northern foothills around Clear Lake. Property owners and politicians have forced Placer Mining Services, a Fluor subsidiary, to stop digging at its mine near Nevada City. Homestake, America's largest producer, and Sonora Mining have also felt pressures against their bulldozing and blasting.

Both companies have responded, to the satisfaction of environmentalists. Homestake uses three huge pressure cookers, called autoclaves, near one of its projects. In them, pure oxygen is pumped through a slurry of gold ore and water to eliminate pollution. By the end of the century, American gold output could reach 200 tons a year, thus making the U.S. the third largest producer behind South Africa (680 tons currently) and the Soviet Union (283 tons).