106 PHYSIOGRAPHY. 



Picrosmine. 



Very sectile. Hardness = 2-5 . . . 3-0. Sp. gr. =2*66, 

 of a cleavable compound variety. 2-596, of a columnar 

 variety. 



Compound Varieties. Massive : composition granular, 

 strongly coherent. If the composition becomes impalpa- 

 ble, the fracture is earthy. The particles of columnar 

 composition are very thin ; fracture splintery. 



1. Before the blow-pipe, it is infusible, but gives out water, becoming 

 first black, then white and opake, and acquires a degree of hardness 

 nearly = 5-0. It is soluble in phosphoric salt, with the exception of a 

 silica-skeleton. When treated with a solution of cobalt, it assumes a 

 pale red color. It appears therefore, to contain water, silica and mag- 

 nesia. 



2. The cleavable varieties have been found, accompanied by Mag- 

 netic Iron, and I 'olomite, in abed in primitive rocks. The only locality 

 hitherto known, is the iron mine called Engelsburg, near Presnitz ia 

 Bohemia. 



3. It is likely that several varieties of Asbestus fall within the present 

 pecies. 



PICTITE. (See Turnerite.) 



PlMELITE. 



Nickel-Ochre, mixed with clay. 



PlNGUlTE. 



Massive : impalpable : resembles Green Iron-Ore. 

 Fiacture large conchoi 'al. 



Lustre resinous. Color, siskin-green and oil-green. Streak 

 paler. Transjucent on the edges. 

 Hardness = 1. Sp. gr. = 2-31. 

 Emits an earthy odor, when moistened. 



1. Analysis. 

 By KARSTEIC. 



Silica 36-90 



Peroxide of iron . ' . . . . 2950 



Protoxide of iron . . . . . 6-10 



Alumina ...... 1'80 



Magnesia , 0-45 



Oxide of manganese . . . . . 0-14 



Water ?..... 25-10 



