Umangite

Umangite

Umangite (purple) on clausthalite. Other copper selenides (green secondaries) and likely chalcomenite (non-metallic blue)
General
Category Selenide mineral
Formula
(repeating unit)
Cu3Se2
Strunz classification 2.BA.15c
Crystal system Tetragonal
Identification
Color Red, bluish red-black
Crystal habit Massive granular
Crystal symmetry Tetragonal
Point group 42m
Space group P421m
Cleavage Distinct on [010] and [001]
Fracture Uneven
Mohs scale hardness 3
Luster Metallic
Streak Black
Diaphaneity Opaque
Specific gravity 5.62 - 6.78
References [1][2][3]

Umangite is a copper selenide mineral, Cu3Se2, discovered in 1891. It occurs only in small grains or fine granular aggregates with other copper minerals of the sulfide group. It has a hardness of 3. It is blue-black to red-violet in color with a black streak. It has a metallic luster.

Umangite is named after the locality of Sierra de Umango, La Rioja province in Argentina. It also occurs at other localities including the Harz Mountains in Germany, and at Skrickerum, Sweden.

See also

References

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