172 PHYSIOGRAPHY. 



Saussurite. 



3. It occurs in a state of perfect purity, or only mixed with a little 

 Sulphur, at the island of Volcano one of the Lipaii group. It is also de- 

 posited from hot springs near Sasso, and from the lagoni of Tuscany. 



4. It is extensively employed in the manufacture of borax. 



SAUSSURITE. Dusclaone Petal! n e-Sp ar. 



Primary form, unknown. 



Cleavage, affords two faces meeting at angles of 124 

 nearly, pretty distinct. Traces parallel to the short diago- 

 nal of that prism. Fracture uneven, splintery. Massive: 

 composition granular . . . impalpable, strongly coherent. 



Lustre pearly, inclining to vitreous upon the faces of 

 cleavage; resinous in compound varieties, particularly when 

 cut and polished. Color white, passing into mountain 

 green, greenish-grey and ash-grey. Streak white. 



Brittle, very difficultly frangible. Hardness =5*5. Sp. 

 gr. =3'256 of a granular variety from Piedmont, 3'342 of 

 a compact variety from the Pays de Vaud. 



1. Before the blow-pipe, it melts with difficulty into a white glass. 

 2. Analysis. 



By SAUSSURE. By KLAPROTH. 



Silica . . . 4900 . . . 44-00 



Alumina . ,. . 24-00 . . . 30-00 

 Lime . . . 10-00 . . . 4-00 



Magnesia . . . 3-75 Potash . 0-25 



Oxide of iron . . 6-50 . . . 12-50 



Oxide of manganese . 0-00 . . . 0-05 



Soda , . . 550 . . . 6-00 



Loss . . . 0-75 . . . 3-20 



3. It is found in primitive mountains, and constitutes with Horn- 

 blende and Augite, the rocks called gabbro and euphotide. It occurs ni 

 large masses upon Monte Rosa, and in its neighborhood; in Corsica; in 

 the Bacher mountain in Lower Stiria, in Baryeuth, &c. In the Uni- 

 ted States at Canaan, (Conn.), it forms a mountain of some miles in 

 extent. 



