Jentschite

General Information:
 Chemical Formula:
TlPbAs2SbS6
 Composition:
(Molecular Weight = 875.57 gm)
Thallium 23.34 % Tl
Antimony 13.91 % Sb
Arsenic 17.11 % As
Lead 23.66 % Pb
Sulfur 21.97 % S 
 Empirical Formula:
TlPbAs2SbS6
 IMA Status:
Approved IMA (Dana # Added)
 Locality:
Lengenbach, Binntal, Switzerland.
 Name Origin:
Named after Franz Jentsch (1868-1908), head of the Binn syndicate that worked the sulfosalt deposit at the Lengenbach quarry.
Physical Properties:
 Cleavage:
[101] Perfect
 Color:
black or dark red.
 Density:
5.24
 Diaphaniety:
Opaque
 Hardness:
2-2.5 - Gypsum-Finger Nail
 Luster:
Sub Metallic
 Streak:
dark red
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