PHYSIOGRAPHY. 49 



Axinite. 



mixture of Talc. Streak white. Transparent . . . trans- 

 lucent, sometimes only on the edges. It exhibits the prop- 

 erty of dichroism. 



Hardness=6-5 . . . 7-0. Sp. gr.=3-271. 



Compound varieties. Massive : composition lamellar, 

 generally a little bent ; faces of composition irregularly 

 streaked. Sometimes the composition is granular and im- 

 palpable. 



1. Before the blow-pipe it melts easily, and with intumescence, into a 

 dark-green glass, which becomes black in the oxidating flame. Some 

 varieties are differently electrified by heat, contiguous to opposite ends 

 of the crystals, and in these also a difference has been observed by 

 HAUY. 



2. Analysis. 



By KL.APROTH. By WIEGMANN. 



Silica . . . 50-50 ... 45-00 



Lime . . . 17-00 . . . 12-50 



Alumina . . . 16-00 . . . 1900 

 Oxide of iron . . 950 . . . 12-25 

 Oxide of manganese . 5-25 . . . 9-00 



Potash . . . 0-25 . . . 0-00 



Magnesia . . . 0-00 . , . 0-25 



Boracic acid . . 00 . . . 2-00 



3. Axinite occurs in beds and veins in primitive countries. It is ac- 

 companied in the former situations by Calcareous Spar, Blende, &c. ; in 

 the latter, chiefly byAugite, Quartz, Feldspar and various metallic min- 

 erals. 



4. It is found in beds at Thum near Ehrenfriedersdorf in Saxony, from 

 whence it has sometimes been called Thumite or Thumerstone. At 

 Kongsberg in Norway, it occurs in veins with Vitreous Silver. Beau- 

 tiful crystals are met with in the veins of various places near Bourg 

 d'Oisans in Dauphiny, at Bareges in the Pyrenees, in Savoy, in the 

 county of Gb'mor in Hungary, and in large, well defined crystals at Bo- 

 tallack in Cornwall. In the latter place, it is found in a massive state, 

 forming a peculiar kind of rock with Garnet and Tourmaline. It is also 

 found at several places in the Hartz. 



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