PHYSIOGRAPHY. 67 



Myargyrite. 



The crystals contain many secondary faces, and have on 

 the whole much the appearance of crystals of Copperas. 



Cleavage, parallel with M, imperfect. Fracture imper- 

 fectly conchoidal. Surface, M deeply streaked parallel to 

 the longer diagonal, P horizontally. 



Lustre intermediate between metallic and metallic ada- 

 mantine.' Color iron-black. Streak dark cherry-red. 

 Opake, except in thin splinters, where it transmits a deep, 

 blood-red color. 



Very sectile. Hardness = 2'0 . . . 2*5. Sp. gr. = 

 5-234. 



1. Before the blow-pipe, it gives results nearly agreeing with thot 



f Red Silver-Ore. 



2. Analysis. 



By ROSE. 



Sulphur ..... 21-93 



Antimony - - - - - 3911 



Silver 36-40 



Copper 1-06 



Iron 0-62 



8. This extremely rare mineral has hitherto been found only in a few 

 single crystals, at Braunsdorf, near Freiberg in Saxony. 



MYSORINE. 



Massive: composition impalpable. Fracture small conchoidal. 

 Color brownish-black, sometimes with a tinge of green and red. 

 Tender. Sp. gr. = 2-620. 



1. It is soluble in the acids, unless when it contains foreign matters ; 

 in which case the solution deposits a reddish precipitate, 

 2. Analysis. 

 By THOMSON. 



Carbonic acid .... 16 70 



Deutoxide of copper - 6075 



Peroxide of iron .... 19-50 



Silica .... 2-10 



