Wattevillite

General Information:
 Chemical Formula:
Na2Ca(SO4)2·4(H2O) (?)
 Composition:
(Molecular Weight = 350.25 gm)
Sodium 13.13 % Na
Calcium 11.44 % Ca
Hydrogen 2.30 % H 
Sulfur 18.31 % S 
Oxygen 54.82 % O 
 Empirical Formula:
Na2Ca(SO4)2·4(H2O)
 Environment:
A questionable species. Associated with other sulfates in a pyritic lignite.
 Locality:
Einigkeit mine, Bauersberg, near Bischofsheim, Bavaria, Germany.
 Name Origin:
Named for Oscar de Watteville of Paris, France.
Physical Properties:
 Color:
white.
 Density:
1.81
 Habits:
Microscopic Crystals - Crystals visible only with microscopes., Acicular - Occurs as needle-like crystals.,
 Luster:
Silky
 Streak:
white
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