California Gold Production Summary
Gold Mining Districts of California
Flanking the main vein system of the Mother Lode on the east and west are two additional zones of mineralization known as the East Belt and West Belt. These belts are shorter and less continuous than the Mother Lode and may be separated from it by 5 to 15 miles of unmineralized country rock (Julihn and Horton, 1938, p. 4) ; nevertheless, they are similar to it genetically and mineralogically and many authors have considered them as part of the Mother Lode. In production reporting, however, the East Belt and West Belt have been considered as being districts separate from the Mother Lode; so to avoid confusion, this distinction is also made in this report.
Gold deposits are not confined to the Mother Lode area, for of the 58 counties in California, significant quantities of gold have been mined in 41. Produc¬tion data for the counties are fairly complete since 1880, but for many individual districts they are spotty and fragmentary, even though many such districts have had substantial production. In the publications of the U.S. Bureau of Mines (1925-34; 1933-66) and U.S. Geological Survey (1904-24) production data for several counties or districts frequently are combined or listed as unapportioned to conceal production of a specific company. Thus in this report the production totals for counties and districts are minimum figures.