Medium-scale Au-Ag epithermal vein deposit, occurring in a blind explosive breccia mass. The orebodies are distributed in the faults and fracture zones at both footwall and hanging wall or in the breccia. Sericite alteration and pyrite alteration occur in the faults and fracture zones. Gold is closely associated with altered faults. The orebodies are veined and banded. The deposit minerals display idiomorphic-hypidiomorphic, metasomatic and solid solution textures and occur in masses, bands, disseminatins, veinlets, stockworks and brecciae. The deposit exhibits four stages of deposition: (1) sericite-quartz-pyrite, (2) gold-pyrite-quartz, (3) gold-sulphides-quartz, and (4) gold-sulphides-quartz-calcite. The third stage is the most important for gold deposition. The temperature for the main deposition stage is 150-360 °C, the pressure is 35-50 MPa. It is interpreted as moderate-low temperature volcanic hydrothermal deposit.
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http://wrgis.wr.usgs.gov/open-file/of03-220/DATABASE/lode_deposits.txt
14 entries listed. 11 valid minerals.