Umangite

Umangite
Umangite (purple) on clausthalite. Other copper selenides (green secondaries) and likely chalcomenite (non-metallic blue)
General
CategorySelenide mineral
Formula
(repeating unit)
Cu3Se2
IMA symbolUm[1]
Strunz classification2.BA.15c
Crystal systemTetragonal
Crystal classScalenohedral (42m)
H-M symbol: (4 2m)
Space groupP421m
Identification
Formula mass348.56 g/mol
ColorRed, bluish red-black
Crystal habitMassive granular
CleavageDistinct on [010] and [001]
FractureUneven
Mohs scale hardness3
LusterMetallic
StreakBlack
DiaphaneityOpaque
Specific gravity5.62–6.78
References[2][3][4]

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.

  1. ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
  2. ^ Webmineral data
  3. ^ Mindat.org
  4. ^ Mineralienatlas