Vulcanite

Vulcanite
General
Category	Telluride mineral
Formula (repeating unit)	CuTe
Strunz classification	2.CB.75
Crystal system	Orthorhombic
Crystal class	Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m)
Space group	Pmnm
Identification
Color	Pale to yellow bronze
Crystal habit	Massive, granular, tabular
Twinning	Common
Cleavage	[hk0] Good, [h0l] Indistinct
Fracture	Sectile - Curved shavings or scrapings produced by a knife blade
Mohs scale hardness	1 - 2
Luster	Metallic
Diaphaneity	Opaque
Specific gravity	7.1
Pleochroism	Very strong, bright yellow to blue-gray
Fusibility	1.5
References

Vulcanite is a rare copper telluride mineral. The mineral has a metallic luster, and is a green or bronze-yellow shade. It has a hardness between 1 and 2 on the Mohs scale (between talc and gypsum). Its crystal structure is orthorhombic.

It is named after the place where it was discovered in 1961, the Mammoth Good Hope Mine in Vulcan (ghost town and district), Gunnison County, Colorado, US. Small deposits have also been discovered in Japan, Russia, Saudi Arabia, and Norway. It occurs with native tellurium, rickardite, petzite and sylvanite.

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