In California, gold miners primarily found gold in the riverbeds and streams flowing from the Sierra Nevada mountains. These rivers, including the American, Feather, Merced, Mokelumne, and Stanislaus rivers, were rich sources of gold particles known as placer deposits. The miners used various methods to extract gold, such as panning, sluicing, and dredging, which depended on the location and conditions of the river. While large amounts of gold were initially discovered in surface deposits, miners later found gold in quartz veins deep underground, leading to the development of underground mining techniques and the construction of mines throughout the region.