Mother lode

Common card · No. 452580

Mother lode is a principal vein or zone of gold or silver ore. In mining terminology, the "mother lode" refers to the bedrock source from which placer gold erodes into streambeds. While the term has entered popular culture through films, video games, and other media, it probably derives from a literal translation of the Spanish veta madre, a phrase common in old Mexican mining. It is also used colloquially to refer to the real or imaginary origin of something valuable or in great abundance. In the United States, the California Mother Lode is a 190-kilometre-long (120 mi), 1.5-to-6-kilometre-wide (0.93 to 3.73 mi) alignment of hard-rock gold deposits in the Sierra Nevada of California, bounded on the east by the Melones Fault Zone. The deposits formed along the suture where the Smartville Block, a Jurassic oceanic terrane, accreted onto North America; hydrothermal fluids emplaced gold-bearing quartz veins during the Early Cretaceous. Discovered in the early 1850s during the California...

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