Polybasite | |
Category: | Sulfosalt minerals |
Imasymbol: | Plb[1] |
Strunz: | 2.GB.15 |
System: | Monoclinic and trigonal polytypes |
Class: | Prismatic (2/m) (same H-M symbol) |
Symmetry: | C2/c |
Colour: | steel black |
Cleavage: | poor on (001) |
Fracture: | uneven |
Mohs: | 1.5–2 |
Lustre: | metallic, adamantine or glimmering |
Streak: | black with reddish tint |
Gravity: | 6–6.2 |
References: | [2] [3] [4] [5] |
Polybasite is a sulfosalt mineral of silver, copper, antimony and arsenic. Its chemical formula is .
It forms black monoclinic crystals (thin, tabular, with six corners) which can show dark red internal reflections. It has a Mohs hardness of 2.5 to 3. It is found worldwide and is an ore of silver. The name comes from the number of base metals in the mineral.