QUICKSILVER IN THE SOUTHERN GOLD RUSH (1800-1848): THE QUESTION OF SOURCES AND SUPPLIES

The opening of the New Almaden quicksilver mine in southern California in 1846 was one of the reasons for the overwhelming success of the California Gold Rush (1849-1860). Mercury was an important component in the extraction of gold from those rich deposits and its usefulness had already been well established earlier in the gold fields of the American South.

One of the more puzzling issues in the gold mining in the American South was the source of the mercury used for the amalgamation and refining processes. The earliest mention of mercury and gold mining is from the Reed Gold (placer) Mine in Cabarrus County. Stephen Ayres (August 1805) described a miner who had a “machine which he had made in Baltimore, to clear the coarse sand from the fine and the gold, and prepare it to be mixed with the mercury.” A later report (1828) by Rothe, who surveyed the gold mines (placer) of the Piedmont, lamented on the loss of gold to the tailings and how the amalgamation with mercury would improve the production. This report would have had wide circulation among the mining interests and may have led to more mercury use in the southeastern gold fields in the 1830’s. Gold mining in the southeastern United States went underground sometime between 1828 and 1830. Processing the pyrite- and chalcopyrite-rich ore required more crushing and processing to extract the gold. Mercury amalgamation, as well as roasting and other techniques, was necessary to reduce the loss of gold to the tailing pile. Miners needed mercury in bulk: the Orange Grove Mine (Virginia) reportedly used 250 to 300 pounds of mercury annually.

The potential sources of mercury for the southern gold fields from 1800 to ~1850 were Spain (via London and the Rothschild family business), Mexico, Chile, and Hungary. Shipped in 76.5 lb cast iron flasks, the mercury would have arrived in Boston, New York City or Baltimore and the bulky flasks would have had to be transshipped by coastal packet, stagecoach, or cart to the mining regions. Records of quicksilver exports from Britain in the 1830s range from hundreds to thousands of quintals (1 quintal = 100 lbs), with the highest being 8572 quintals in 1835. Although some of this may have been used in the vermilion industry in New York, a portion of this may have found its way south into the gold fields as well as the newly established Federal mints who were coining the golden metal.