Ag3Cu12Sb4S13

Ag3Cu12Sb4S13 is a complex mineral belonging to the tetrahedrite group. It is a member of the sulfosalt family, characterized by its intricate crystal structure and metallic luster. The chemical formula indicates a significant presence of silver (Ag), copper (Cu), antimony (Sb), and sulfur (S) in its composition. This specific mineral is often referred to as "tetrahedrite" or a silver-bearing variety of tetrahedrite, though its precise stoichiometry can vary.

This mineral is typically found in hydrothermal veins and is associated with other sulfide minerals. Its formation is generally linked to moderate to low-temperature hydrothermal processes. Ag3Cu12Sb4S13 is known for its dark gray to black color and its opaque nature. Crystals are often tetrahedral or dodecahedral in habit, though massive forms are also common.

In terms of physical properties, it possesses a relatively high specific gravity due to the presence of heavy elements like silver and copper. Its hardness is typically around 3 to 3.5 on the Mohs scale. While not a primary ore of any single metal, it can contribute to the overall silver and copper content of a mineral deposit. Its identification often requires detailed mineralogical analysis due to its complex chemistry and potential for solid solution with other members of the tetrahedrite group.