Kelyanite

General Information:
 Chemical Formula:
Hg+16Hg++20Sb3(Cl,Br)9O28
 Composition:
(Molecular Weight = 8,398.00 gm)
Mercury 85.99 % Hg
Antimony 4.35 % Sb
Bromine 0.95 % Br
Chlorine 3.38 % Cl
Oxygen 5.33 % O 
 Empirical Formula:
Hg16Hg20Sb3Cl8BrO28
 Environment:
Oxidation zone of stibnite-cinnabar ores.
 IMA Status:
Approved IMA 1982
 Locality:
Kelyan deposit, Buryatia, Ural Mountains, Russia.
 Name Origin:
Named for the locality.
Physical Properties:
 Cleavage:
None
 Color:
brown or reddish brown.
 Density:
8.51 - 8.63, Average = 8.57
 Diaphaniety:
Nearly opaque
 Habits:
Granular - Generally occurs as anhedral to subhedral crystals in matrix., ,
 Streak:
reddish brown
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