When mixed with gold-bearing dust, and heated, the mercury burned away, leaving melted clusters of gold. Miners often burned the mix in their cabins, breathing in toxic fumes. Gold is an element distributed pretty much everywhere on the globe. The first serious American gold rush occurred in Georgia in 1829. There are gold rushes going on right now in Indonesia, Guyana and Brazil.
Hikers can still pan gold out of the muddy Potomac River.
One celebrated example is the merchant who, seeing how fast miners' pants wore out, began making them out of tough tent canvas, eventually securing them at key points with copper rivets. He was Levi Strauss, the inventor of Levi's. But John Sutter, the man who might have profited most, the man on whose land gold was found, became a classic victim of the rush. A German immigrant, kindly, enterprising, and surely one of the most unlucky businessmen in history, Sutter was constantly starting new commercial schemes with folks like Marshall. Characteristically, Sutter commissioned him to build a sawmill too far up the American River to be practical.