Jarosewichite

Jarosewichite is a manganese arsenate hydroxide mineral with a chemical formula of Mn2+3Mn3+(AsO4)(OH)6.[1]  It was originally discovered in a metamorphosed Zn-Mn deposit in Franklin, New Jersey. It was named after Eugene Jarosewich, emeritous chemist at the Smithsonian Institution.
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General Information:
 Chemical Formula:
Mn++3Mn+++(AsO4)(OH)6
 Composition:
(Molecular Weight = 460.72 gm)
Manganese 47.70 % Mn
Arsenic 16.26 % As
Hydrogen 1.31 % H 
Oxygen 34.73 % O 
 Empirical Formula:
Mn2+3Mn3+(AsO4)(OH)6
 Environment:
Metamorphosed Zn-Mn deposit.
 IMA Status:
Approved IMA 1982
 Locality:
Franklin, Sussex County, New Jersey, USA.
 Name Origin:
Named for Eugene Jaroswich (1926-), chief chemist, Department of Mineral Sciences, National Museum of Natural History, Smithsonian Institution.
Physical Properties:
 Cleavage:
None
 Color:
dark red.
 Density:
3.66
 Habits:
Aggregates - Made of numerous individual crystals or clusters., Divergent - Crystals radiate from a center without producing stellar forms.,
 Hardness:
4 - Fluorite
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous (Glassy)
 Streak:
reddish orange
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