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OETHOEHI 



I A 1= 119° 10' and £ 



1 



I A i-3 = 150° i-i /\ 

 i-3 A i-3 = 120° 50' 



Cleavage, i-i distinct ; i-l and indis 

 Crystals, foliated parallel with 0. 



Transpan 

 Dichroic, blue to yellow, but 



Lustre vitr' 

 Colour, blue 



Spec. grav. = 



Hardness 

 Fuses at 5-5, loses 



Chemical Compos 



Silica, SiO-2, 

 Alumina, AI2O3, 

 Ferrous Oxide, FeO, . 

 Magnesia, MgO, 

 Calcium Oxide, CaO, 

 Manganese Oxide, MnO. 

 Ignition, (H2O), 



