Hejtmanite

General Information:
 Chemical Formula:
Ba(Mn,Fe++)2TiO(Si2O7)(OH,F)2
 Composition:
(Molecular Weight = 514.71 gm)
Barium 26.68 % Ba
Titanium 9.30 % Ti
Manganese 16.01 % Mn
Iron 5.43 % Fe
Silicon 10.91 % Si
Hydrogen 0.29 % H 
Oxygen 29.53 % O 
Fluorine 1.85 % F 
 Empirical Formula:
BaMn2+1.5Fe2+0.5TiO(Si2O7)(OH)1.5F0.5
 IMA Status:
Approved IMA
Physical Properties:
 Cleavage:
[???] Perfect
 Color:
golden yellow or orange brown.
 Density:
4.016
 Diaphaniety:
Translucent
 Hardness:
4.5 - Between Fluorite and Apatite
 Luster:
Vitreous (Glassy)
 Streak:
brown yellow
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