Magnesiohastingsite

General Information:
 Chemical Formula:
NaCa2(Mg4Fe+++)Si6Al2O22(OH)2
 Composition:
(Molecular Weight = 864.69 gm)
Sodium 2.66 % Na
Calcium 9.27 % Ca
Magnesium 11.24 % Mg
Aluminum 6.24 % Al
Iron 6.46 % Fe
Silicon 19.49 % Si
Hydrogen 0.23 % H 
Oxygen 44.41 % O 
 Empirical Formula:
NaCa2Mg4Fe3+(Si6Al2O22)(OH)2
 IMA Status:
Approved IMA 1978
Physical Properties:
 Cleavage:
[???] Good
 Color:
green.
 Density:
3.225
 Diaphaniety:
Subopaque
 Hardness:
5-6 - Between Apatite and Orthoclase
 Luster:
Vitreous (Glassy)
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