Tellurobismuthite

Tellurobismuthite, or tellurbismuth,^[5] 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.^[4]

Tellurobismuthite
Tellurobismuthite. Locality: Kutemajärvi mine, Orivesi, Western and Inner Finland Region, Finland
General
Category	Sulfide mineral
Formula	Bi2Te3
IMA symbol	Tbi[1]
Strunz classification	2.DC.05
Crystal system	Trigonal
Crystal class	Hexagonal scalenohedral (3m) H-M symbol: (3 2/m)
Space group	R3m
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
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	[2][3][4]

Discovery and occurrence

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.^[2]

It occurs in low sulfur hydrothermal gold-quartz veins and occurs with native gold, native bismuth, gold tellurides, tetradymite, altaite, chalcopyrite and pyrrhotite.^[4]

See also

• List of minerals