Achávalite

Achávalite
Black metallic crystals of achávalite from Cacheuta Mine, Mendoza, Argentina
General
CategorySelenide mineral
Formula(Fe,Cu)Se
IMA symbolAhv
Strunz classification2.CC.05
Crystal systemHexagonal
Crystal classDihexagonal dipyramidal (6/mmm)
H-M symbol: (6/m 2/m 2/m)
Space groupP63/mmc
Unit cella = 3.636, c = 5.946 [Å], Z = 2
Identification
Formula mass134.81 g/mol
ColorDark grey
Mohs scale hardness2.5
LusterMetallic
StreakGrey-black
DiaphaneityOpaque
Specific gravity6.53
References

Achávalite is a selenide mineral that is a member of the nickeline group. It has only been found in a single Argentinian mine system, being first discovered in 1939 in a selenide deposit. The type locality is Cacheuta mine, Sierra de Cacheuta, Mendoza, Argentina.