The tetrahedral faces are in many instances modified by other crystal forms giving the crystals multiple facets while still retaining the basic tetrahedral shape. Most members of the tetrahedrite group belong to this informal group. Tetrahedrite can form interesting and handsome mineral specimens. Often it will contain a certain percentage of silver and be used as a minor ore. The multi-faceted tetrahedral crystals as well as the flat faced simple tetrahedral crystals can be very striking and a real pleasure for mineral collectors to own.
Color is black to steel gray to silver.
Luster is metallic. Transparency crystals are opaque. Twinning is occassionally seen. Also massive and granular. Cleavage is absent.