Nagelschmidtite

General Information:
 Chemical Formula:
Ca7(SiO4)3(PO4)2
 Composition:
(Molecular Weight = 746.74 gm)
Calcium 37.57 % Ca
Silicon 11.28 % Si
Phosphorus 8.30 % P 
Oxygen 42.85 % O 
 Empirical Formula:
Ca7(SiO4)3(PO4)2
 Environment:
Sedimentary phosphate deposits.
 IMA Status:
Approved IMA 1977
 Locality:
Lowermost portion of the Hatrarum formation, Israel.
 Name Origin:
Named for G. Nagelschmidt, who first described the synthetic compound in 1937.
Physical Properties:
 Cleavage:
[001] Good
 Color:
brown, colorless, yellowish white, or light yellow.
 Density:
3.065
 Diaphaniety:
Transparent
 Habits:
Anhedral Grains - Granular minerals without the expression of crystal shapes, ,
 Luster:
Vitreous (Glassy)
 Streak:
white
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