The zone contains hundreds of mines and prospects, including some of the best-known historic mines of the gold-rush era. The Mother Lode coincides with the suture line of a terrane, the Smartville Block. The California Mother Lode is a zone from 1.5 to 6 kilometres (0.93 to 3.73 mi) wide and 190 kilometres (120 mi) long, between Georgetown on the north and Mormon Bar on the south. It was discovered in the early 1850s, during the California gold rush. In the United States, Mother Lode is most famously the name given to a long alignment of hard-rock gold deposits stretching northwest-southeast in the Sierra Nevada of California, bounded on the east by the Melones Fault Zone. Veta madre, for instance, is the name given to an 11-kilometre-long (6.8 mi) silver vein discovered in 1548 in Guanajuato, New Spain (modern-day Mexico). The term probably came from a literal translation of the Spanish veta madre, a term common in old Mexican mining. The term is also used colloquially to refer to the real or imaginary origin of something valuable or in great abundance. Mother lode is a principal vein or zone of gold or silver ore. (Right) Crystalline gold specimen from the California Mother Lode, probably from Tuolumne County (5.3 x 2.7 x 2.4 cm). They are typical of larger nuggets found by the early California gold rush placer miners (each ~1.6 x 1.1 x 0.3 cm). (Left) Two water-worn gold nuggets from Tuolumne County.

Motherlode mine gold nuggets per hour