Zhemchuzhnikovite

Zhemchuzhnikovite is a mineral of organic origin; formula NaMg(FeAl)C2O4.8H2O. It forms smokey green crystals with a vitreous lustre and is found in Russian coal mines. It is named after Yury Zhemchuzhnikov [1], a Russian clay mineralogist.
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General Information:
 Chemical Formula:
NaMg(Al,Fe+++)(C2O4)3·8(H2O)
 Composition:
(Molecular Weight = 494.00 gm)
Sodium 4.65 % Na
Magnesium 4.92 % Mg
Aluminum 3.28 % Al
Iron 4.52 % Fe
Hydrogen 3.26 % H 
Carbon 14.59 % C 
Oxygen 64.77 % O 
 Empirical Formula:
NaMgAl0.6Fe3+0.4(C2O4)3·8(H2O)
 Environment:
Lignite or coal mines.
 IMA Status:
Approved IMA 1963
 Locality:
Chaitumusuk deposits, Lena River, Siberia.
 Name Origin:
Named for Yurii Apollonovich Zhemchezhnikov (1885-1957), Russian geologist.
Physical Properties:
 Cleavage:
[0001] Good
 Color:
gray green or violet.
 Density:
1.69
 Diaphaniety:
Transparent to Translucent
 Habits:
Acicular - Occurs as needle-like crystals., Fibrous - Crystals made up of fibers., Water Soluble - Water soluble mineral.
 Hardness:
2 - Gypsum
 Luster:
Vitreous (Glassy)
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