Teallite

Teallite is a sulfide mineral of tin and lead with chemical formula: PbSnS2. It occurs in hydrothermal veins and is sometimes mined as an ore of tin. Teallite forms soft silvery grey mica-like plates and crystallizes in the orthorhombic system. The Mohs hardness is 1.5 to 2 and the specific gravity is 6.4.
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General Information:
 Chemical Formula:
PbSnS2
 Composition:
(Molecular Weight = 390.04 gm)
Tin 30.44 % Sn
Lead 53.12 % Pb
Sulfur 16.44 % S 
 Empirical Formula:
PbSnS2
 Locality:
Silver mines of Santa Rosa, Antequera, Bolivia.
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
lead gray, grayish black, or iron gray.
 Density:
6.4
 Diaphaniety:
Opaque
 Habits:
Micaceous - Platy texture with "flexible" plates., ,
 Hardness:
1.5-2 - Talc-Gypsum
 Luster:
Metallic
 Streak:
black
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