162 PHYSIOGRAPHY. 



Red Silver. 



3. Face of composition parallel to n, axis of revolution 

 perpendicular to it. The individuals are sometimes con- 

 tinued beyond the face of composition. Massive : compo- 

 sition granular, of various sizes of individuals, strongly con- 

 nected. If the composition becomes impalpable, fracture 

 is uneven 3 even, or flat conchoidal. Plates, superficial 

 coatings. 



1. When heated before the blow-pipe, it first decrepitates, then melts, 

 burning with a bluish flame, and emitting sulphurous acid together 

 with the white smoke of antimony. By continuing the heat, a globule 

 of silver is obtained. Its powder heated in nitric acid, turns black, 

 emits red fumes, and dissolves leaving behind some sulphur and oxide 

 of antimony. The solution yields with water a white precipitate, on 

 the separation of which, muriatic acid occasions the deposition of chlo- 

 ride of silver. 



2. Analysis. 



By BONSDORFF. 



A var. from Andreasberg. 



Sulphur . 16-609 



Antimony 22-846 



Silver 58-949 



Earthy matter . . . . . . . 0-299 



3. It has hitherto been found in veins associated with various other 

 ores of silver, particularly with Proustite, and Native Silver, also with Ga- 

 lena, Blende, and several species of Pyrites. 



4. It is found in beautiful crystals, at Andreasberg in the Hartz, and 

 is also met with at Schemnitz, Cremnitz, Nagybanya, &c. in Hungary, 

 in Alsace and Dauphiny in France and at Kongsberg in Norway. It 

 occurs in the greatest abundance at Zacatecas in Mexico, from whence 

 very splendid crystallizations are procured. 



5. It is of considerable value as an ore of silver. The mine of Veta- 

 Negra, near Sombrerete, produced in the space of a few months 700,000 

 marcs of silver from this species. 



RED VITRIOL. (See Cob alt- Vitriol.) 



