232 PHYSIOGRAPHY. 



Thorite. 



THORITE. Peritomoiis Tungstic-Bary te. 



Primary form. Octahedron with a square base ? P on 

 P=120'. 



Secondary form. 



Fig. 434. 



Cleavage, parallel with e, imperfect. Fracture uneven 

 and splintery. 



Lustre resinous. Color brown. Streak yellowish grey 

 to brown. 



Hardness=5-0 . . . 5-50. Sp. gr.=4-5 . . . 4-6. 



1. Alone, before the blow-pipe, it is infusible, but becomes paler. It 

 melts slowly with borax into a colorless glass. 



2. Analysis. 

 Thorina 57-41 



Lime 2-58 



Oxide of iron ....'.. 3-40 



Oxide of manganese 2-39 



Magnesia 0-36 



Oxide of uranium 161 



Oxide of lead 0-80 



Oxide of tin 0-01 



Silica 18-98 



Water 9-50 



Potash 0-14 



Soda 0-10 



Alumina .' 0-06 



Powder not examined T7Q 



