OllDER IX. DODECAHEDRAL MERCURY. 431 



ing upon the charcoal. It is soluble in nitric acid, but the 

 solution yields a white precipitate, if farther diluted. It 

 crystallises easily from fusion. 



2. Octahedral Bismuth occurs chiefly in veins in gneiss 

 and clay-slate, and is accompanied by ores of silver, cobalt, 

 tin, &c. The Bismuth-ochre, which in a great measure 

 depends upon the presence of that metal, is likewise often 

 found along with it. 



3. Its chief localities are several of the Saxon and Bo- 

 hemian silver and cobalt mines at Schneeberg, Armaberg, 

 Marienberg, Johanngeorgenstadt, Joachimsthal, &c. Large 

 cleavable varieties have been found in the tin mine of Al- 

 tenberg. It is found besides at Bieber in the principality 

 of Hanau, in the Sophia mine at Wittichen in Fiirstenberg, 

 at Loling in Carinthia, at Fahlun in Sweden, Modum in 

 Norway, in France, &c. It occurs with ores of cobalt in 

 Wheal Sparnon near Redruth, and with prismatic Bismuth- 

 glance at Carrock in Cumberland. 



4. It enters into the composition of several metallic al- 

 loys used in the arts, and is employed in certain technical 

 or metallurgic operations. 



GENUS V. MERCURY. 

 1. DODECAHEDRAL MERCORY. 



Dodecahedral Mercury, or Native Amalgam. JAM. Syst. 

 Vol. III. p. 86. Man. p. 261. Native Amalgam. PHILL. 

 p. 357. Natiirlich Amalgam. WEKN. Hoffm. H. B. 

 III. 2. S. 21. Amalgam. HAUSM. I. S. 107- Amal- 

 gam. LEONH. S. 207. Mercure argental. HAUY. 

 Traite', T. III. p. 432. TabL comp. p. 77. Traite', 

 2de Ed. T. III. p. 307. 



Fundamental form. Hexahedron. Vol. I. Fig. I. 



Simple forms. H (z) ; O (r\ Vol. I. Fig. 2 ; D, 

 Vol. I. Fig. 31. ; Aa (Q f Vol. I Fig. 32.; Ci 

 (,9), Vol. I. Fig. 34.; Ti (Z), Vol. I. Fig. 35. 



Char, of Comb. Tessular. 



