Umangite

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.
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n. umangite, copper selenide occurring only in small grains or aggregates with other copper minerals (Minerals)

General Information:
 Chemical Formula:
Cu3Se2
 Composition:
(Molecular Weight = 348.56 gm)
Copper 54.69 % Cu
Selenium 45.31 % Se
 Empirical Formula:
Cu3Se2
 Name Origin:
Named after the Sierra de Umango in Argentina.
Physical Properties:
 Cleavage:
[010] Distinct, [001] Distinct
 Color:
blue black, brownish black, or red violet.
 Density:
5.62 - 6.78, Average = 6.2
 Diaphaniety:
Opaque
 Habits:
Massive - Granular - Common texture observed in granite and other igneous rock., ,
 Hardness:
3 - Calcite
 Luster:
Metallic
 Streak:
black
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