Lavrentievite

General Information:
 Chemical Formula:
Hg3S2(Cl,Br)2
 Composition:
(Molecular Weight = 759.03 gm)
Mercury 79.28 % Hg
Sulfur 8.45 % S 
Bromine 5.26 % Br
Chlorine 7.01 % Cl
 Empirical Formula:
Hg3S2Cl1.5Br0.5
 Locality:
Arzak mercury deposits, Tuva, Siberia, Russia.
 Name Origin:
Named for Michail Alexeevich Lavrentiev (1900-1980), Russian mathematician and academician, founder of the Siberian Academy of Science.
Physical Properties:
 Color:
grayish black or light yellow.
 Density:
7.26 - 7.5, Average = 7.38
 Diaphaniety:
Opaque
 Habits:
Microscopic Crystals - Crystals visible only with microscopes., ,
 Luster:
Metallic
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