Nelenite

Nelenite ((Mn,Fe)16Si12As3O36(OH)17) is a mineral found in New Jersey.
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General Information:
 Chemical Formula:
(Mn,Fe++)16Si12As+++3O36(OH)17
 Environment:
Dimorphous with schallerite.
 IMA Status:
Approved IMA 1982
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
brown.
 Density:
3.46
 Diaphaniety:
Transparent to Translucent
 Hardness:
5 - Apatite
 Luster:
Vitreous (Glassy)
 Streak:
light brown
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