Ferribarroisite

General Information:
 Chemical Formula:
CaNa(Fe++,Mg)3Fe+++2[AlSi7O22](OH)2
 Composition:
(Molecular Weight = 928.23 gm)
Sodium 2.48 % Na
Calcium 4.32 % Ca
Magnesium 1.96 % Mg
Aluminum 2.91 % Al
Iron 25.57 % Fe
Silicon 21.18 % Si
Hydrogen 0.22 % H 
Oxygen 41.37 % O 
 Empirical Formula:
CaNaFe2+2.25Mg0.75Fe3+2(Si7AlO22)(OH)2
 IMA Status:
Approved IMA 1997
Physical Properties:
 Diaphaniety:
Transparent to Translucent
 Hardness:
5-6 - Between Apatite and Orthoclase
 Luster:
Vitreous (Glassy)
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