Kempite

General Information:
 Chemical Formula:
Mn2Cl(OH)3
 Composition:
(Molecular Weight = 196.35 gm)
Manganese 55.96 % Mn
Hydrogen 1.54 % H 
Chlorine 18.06 % Cl
Oxygen 24.45 % O 
 Empirical Formula:
Mn2+2Cl(OH)3
 Environment:
Oxidized portions of manganese deposits.
 Locality:
Alum Rock Park, 7 miles NE of San Jose, Santa Clara Co. California.
Physical Properties:
 Cleavage:
None
 Color:
emerald green.
 Density:
2.94
 Diaphaniety:
Translucent to Opaque
 Habits:
Crystalline - Fine - Occurs as well-formed fine sized crystals., Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).,
 Hardness:
3.5 - Copper Penny
 Luminescence:
Non-fluorescent.
 Streak:
light green
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