Vernadite

General Information:
 Chemical Formula:
(Mn++++,Fe+++,Ca,Na)(O,OH)2·n(H2O)
 Environment:
Marine and fresh water iron-manganese crusts and concretions, often in relict bacterial forms.
 Locality:
Somewhere in Russia.
 Name Origin:
Named for Vladimir Ivanovich Vernadskii (1863-1945), Russian natrualist and geochemist.
Physical Properties:
 Color:
black or chocolate brown.
 Density:
3
 Diaphaniety:
Opaque
 Streak:
chocolate brown
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