Santaclaraite

General Information:
 Chemical Formula:
CaMn++4Si5O14(OH)2·(H2O)
 Composition:
(Molecular Weight = 676.28 gm)
Calcium 5.93 % Ca
Manganese 32.49 % Mn
Silicon 20.76 % Si
Hydrogen 0.60 % H 
Oxygen 40.22 % O 
 Empirical Formula:
CaMn2+4Si5O14(OH)2·(H2O)
 Locality:
Pennsylvania mine, SW side of San Antonio Valley, 4 miles ENE of Mount Hamilton, Santa Clara Co., California.
 Name Origin:
Named after it's locality.
Physical Properties:
 Cleavage:
[100] Good, [010] Good
 Color:
light pink or reddish orange.
 Density:
3.31
 Diaphaniety:
Transparent to Translucent
 Hardness:
6.5 - Pyrite
 Luster:
Vitreous (Glassy)
 Streak:
light pink
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