Schallerite

General Information:
 Chemical Formula:
Mn++16[As+++O2OH][Si12O30](OH)14
 Composition:
(Molecular Weight = 2,305.90 gm)
Manganese 38.12 % Mn
Silicon 14.62 % Si
Arsenic 9.75 % As
Hydrogen 0.74 % H 
Oxygen 36.77 % O 
 Empirical Formula:
Mn2+16As3Si12O36(OH)17
 Environment:
Metamorphosed zinc deposit. Dimorphous with nelenite.
 Locality:
700 ft level, Franklin mine, Franklin, Sussex Co., New Jersey, USA.
 Name Origin:
Named for Wakdemar Theodore Shaller ((1852-1967), mineralogist, U. S. Geological Survey.
Physical Properties:
 Cleavage:
[0001] Good
 Color:
light brown or reddish brown.
 Density:
3.37
 Diaphaniety:
Translucent
 Habits:
Massive - Uniformly indistinguishable crystals forming large masses., ,
 Hardness:
4.5-5
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous - Waxy
 Streak:
light brown
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