Aktashite

General Information:
 Chemical Formula:
Cu6Hg3As4S12
 Composition:
(Molecular Weight = 1,667.52 gm)
Copper 22.86 % Cu
Mercury 36.09 % Hg
Arsenic 17.97 % As
Sulfur 23.08 % S 
 Empirical Formula:
Cu6Hg3As4S12
 IMA Status:
Approved IMA
 Locality:
TL: Gal-Kyaya deposit, Yakutia, and Aktash deposit, Altai Mts., Russia.
 Name Origin:
Named after the locality.
Physical Properties:
 Cleavage:
None
 Color:
grayish black.
 Density:
5.5
 Diaphaniety:
Opaque
 Habits:
Microscopic Crystals - Crystals visible only with microscopes., Anhedral Grains - Granular minerals without the expression of crystal shapes, Euhedral Crystals - Occurs as well-formed crystals showing good external form.
 Hardness:
3.5 - Copper Penny
 Luster:
Metallic
 Streak:
black
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