Jahnsite-(MnMnMn)

General Information:
 Chemical Formula:
MnMnMn2Fe+++2(PO4)4(OH)2·8(H2O)
 Composition:
(Molecular Weight = 889.47 gm)
Manganese 24.71 % Mn
Iron 12.56 % Fe
Phosphorus 13.93 % P 
Hydrogen 2.04 % H 
Oxygen 46.77 % O 
 Empirical Formula:
Mn2+Mn2+Mn2+2Fe3+2(PO4)4(OH)2·8(H2O)
 IMA Status:
Approved IMA
 Locality:
Stewart mine, Pala, San Diego County, California, USA.
 Name Origin:
Named for Richard H. Jahns (1915-1983), mineralogist and pegmatite expert, Stanford University, Palo Alto, California, USA.
Physical Properties:
 Cleavage:
None
 Color:
brown, purplish brown, yellow, or yellow orange.
 Diaphaniety:
Transparent to Translucent
 Hardness:
4 - Fluorite
 Luster:
Vitreous - Adamantine
 Streak:
white
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