Wightmanite

General Information:
 Chemical Formula:
Mg5(BO3)O(OH)5·2(H2O)
 Composition:
(Molecular Weight = 376.21 gm)
Magnesium 32.30 % Mg
Boron 5.75 % B 
Hydrogen 2.41 % H 
Oxygen 59.54 % O 
 Empirical Formula:
Mg5(BO3)O(OH)5·2(H2O)
 Environment:
Metamorphosed limestone.
 IMA Status:
Approved IMA 1962
 Locality:
Crestmore Quarry, 5 miles NW of Riverside, Riverside Co., California.
Physical Properties:
 Cleavage:
[010] Perfect, [100] Distinct
 Color:
colorless or light green.
 Density:
2.6
 Diaphaniety:
Transparent
 Hardness:
5.5 - Knife Blade
 Luster:
Vitreous (Glassy)
 Streak:
white
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