Vikingite

General Information:
 Chemical Formula:
Ag5Pb8Bi13S30
 Composition:
(Molecular Weight = 5,875.67 gm)
Silver 9.18 % Ag
Bismuth 46.24 % Bi
Lead 28.21 % Pb
Sulfur 16.37 % S 
 Empirical Formula:
Ag5Pb8Bi13S30
 IMA Status:
Approved IMA 1977
 Locality:
Ivigtut, Greenland.
 Name Origin:
Named for the Vikings, who settled Greenland in the tenth century.
Physical Properties:
 Color:
gray.
 Density:
6.94
 Diaphaniety:
Opaque
 Habits:
Microscopic Crystals - Crystals visible only with microscopes., Lamellar - Thin laminae producing a lamellar structure.,
 Hardness:
3.5 - Copper Penny
 Luster:
Metallic
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