Tellurobismuthite

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Tellurobismuthite
General
Category Sulfide mineral
Formula
(repeating unit)
Bi2Te3
Strunz classification 2.DC.05
Crystal system Trigonal
Hexagonal scalenohedral class
Unit cell a = 4.43, c = 29.91 [Å]; Z = 3
Identification
Color Pale lead-gray; white in polished section
Crystal habit Foliated masses and irregular plates
Crystal symmetry Trigonal
H-M symbol: (32/m)
Space group: R3m
Cleavage Perfect on {0001}
Tenacity Flexible, sectile
Mohs scale hardness 1.5 - 2
Luster Metallic
Streak Lead gray
Diaphaneity Opaque
Specific gravity 7.815
References [1][2][3]

Tellurobismuthite is a telluride mineral: bismuth telluride (Bi2Te3). It crystallizes in the trigonal system. There are natural cleavage planes in the (0001) direction as the crystal is effectively lamellar (layered) in that plane. The Mohs hardness is 1.5 - 2 and the specific gravity is 7.815. It is a dull grey color, which exhibits a splendent luster on fresh cleavage planes.[3]

Discovery and occurrence[edit]

It was first described in 1815 and type localities include the Mosnap mine in Toke, Telemark, Norway; the Little Mildred mine, Sylvanite District, Hidalgo County, New Mexico and the Boly Field Mine, Dahlonega, Lumpkin County, Georgia.[1]

It occurs in low sulfur hydrothermal gold-quartz veins and occurs with native gold, native bismuth, gold tellurides, tetradymite, altaite, chalcopyrite and pyrrhotite.[3]

See also[edit]

References[edit]

  • D. M Chizhikov and V. P. Shchastlivyi, 1966, Tellurium and Tellurides, Nauka Publishing, Moscow