Cordilleran Section - 97th Annual Meeting, and Pacific Section, American Association of Petroleum Geologists (April 9-11, 2001)

Paper No. 0
Presentation Time: 1:50 PM


HILL, Robert L., KOHLER, Susan L., HIGGINS, Chris T. and YOUNGS, Leslie G., California Department of Conservation, Div of Mines and Geology, 801 K Street, MS 08-38, Sacramento, CA 95814,

California’s rich heritage has been greatly influenced by its history of gold-mining. From 1848 until 1999, when passed by Nevada, California led the nation in cumulative gold production with about 118 million troy ounces. The first known discovery of gold occurred around 1775 in Imperial County. Word of California’s gold resources did not spread universally, however, until James Marshall’s discovery in 1848 at Coloma. No other single event in the history of California has had such a profound influence on the state’s development. For example, its non-Native American population rose from about 7,000 in 1847 to 93,000 in 1850, when California became a state. Many permanently settled in California as farmers, ranchers, merchants, and manufacturers. By the mid-1860s, the rich surface and river placers became exhausted. Hydraulic mining became dominant, but also caused rivers in the Central Valley to fill with sediment, which instigated California’s first major environmental controversy. In 1884, the Sawyer Decision effectively ended hydraulic mining by prohibiting dumping of mining debris into these rivers. Subsequently, technology, economics, and political decisions periodically enhanced California’s gold production. Underground mines and dredging became dominant from the 1890s until 1942, when most underground mines were shut down by the government. Production peaked during the early 1900s and the 1930s, but declined significantly after 1950. Production intensified in the 1980s after deregulation of gold prices stimulated a modern gold rush; mines opened in both historic gold districts and virgin areas. Since 1990, annual gold production has ranged from about 600,000 to 1,100,000 troy ounces. California has been in the forefront of mining technology throughout its gold-mining history. The Pelton wheel and hydraulic mining were developed here. Since the 1980s, open-pit mining, heap-leaching, and other new technology have made formerly uneconomic deposits profitable. Mandatory reclamation of these modern mines has also benefited from this technological progress. The future of gold-mining in California will depend on economics, land-use policy, technology, regulation, and public attitudes.