Description: Tetrahedrite group Neves-Corvo Mine, Santa Bárbara de Padrões, Castro Verde, Beja District, Portugal crystal 2 mm Tetrahedrite-tennantite crystal surrounded by galena. Some authors suggest that these assemblages in volcanogenic sulfide deposits come from the mixing of hydrothermal fluids with cold seawater, with precipitation of galena-tetrahedrite group association.

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