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Tiemannite

Tiemannite
Tiemannit.jpg
General
Category Selenide mineral
Formula
(repeating unit)
HgSe
Strunz classification 2.CB.05a
Dana classification 02.08.02.04
Crystal system Isometric
Crystal class Hextetrahedral (43m)
H-M symbol: (4 3m)
Space group F43m
Identification
Color Steel-gray to black
Crystal habit Massive and as euhedral crystals
Cleavage none
Mohs scale hardness 2.5
Luster Metallic
Streak grayish black
Diaphaneity opaque
Specific gravity 8.19 - 8.47
References

Tiemannite is a mineral, mercury selenide, formula HgSe. It occurs in hydrothermal veins associated with other selenides, or other mercury minerals such as cinnabar, and often with calcite. Discovered in 1855 in Germany, it is named after Johann Carl Wilhelm Tiemann (1848–1899).


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Wikipedia

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