National Geographic : 1974 Jun
Invisible gold hides in the hills near Carlin, scattered in flecks too small to be visible except under an electron microscope -and too small to mine until the advent of modern technology. Multiple explosions (above, left) rip loose chunks of gold bearing rock. Crushed ore surrenders the metal to a cyanide solution; zinc is added to precipitate the gold, which is then smelted. Working around the clock, Carlin pro cesses 4,000 tons of ore to make a 50-pound button (above). Periodically, workers toss their gloves and coveralls into the furnace to recover any vestiges of absorbed metal. Carlin, second among North America's gold mines only to South Dakota's fabulous ly rich Homestake, was described in detail in the May 1968 GEOGRAPHIC. High-quality gemstones glisten under the hose of Dowell Ward, Jr., owner of Ameri ca's most productive turquoise mine (left). Ward paid $20,000 for his Crescent Valley holdings in 1956 and has since refused to sell out for three million dollars. The bulk of the Silver State's under ground wealth lies less in gold and tur quoise, however, than in such commodities as lead, magnesite, and especially copper, which accounts for nearly 60 percent of Nevada's income from minerals.