430 PHYSIOGRAPHY. CLASS 11. 



GENUS IV. BISMUTH. 

 1. OCTAHEDRAL BISMUTH. 



Octahedral Bismuth. JAM. Syst. Vol. III. p. 107- Man. 

 p. 260. Native Bismuth. PHILL. p. 272. Gediegen 

 Wismutb. WE UN. Hoffm. H. B. IV. I. S. 65. Ge- 

 diegen Wismuth. HAUSM. I. S. 123. Gediegen-Wis- 

 muth. LEONH. S. 211. Bismuth natif. HAUY. Traite*, 

 T. IV. p. 184. Tabl. comp. p. 105. Traite, 2de Ed. 

 T. IV. p. 202. 



Fundamental form. Hexahedron. VoL I. Fig. 1. 



Simple forms. , Bieber near Hanau ; -- -, 



Vol. I. Fig. 13. 14. ; D, Vol. I. Fig. 31. 

 Char, of Comb. Semi-tessular, with inclined faces. 

 Combinations. 1. Fig. 158. 



Cleavage, octahedron, perfect, and easily obtained. 



Fracture not observable. Surface rough, gene- 



rally covered with a grey oxide. 

 Lustre metallic. Colour silver-white, much inclin- 



ing to reel, subject to tarnish. Streak unchanged. 

 Sectile, almost malleable. Hardness = 2-0 ... 2-5. 



Sp. Gr. = 9'737, a variety from Altenberg ; = 



9-612, the melted metal. 



Compound Varieties. Imbedded feathery and 

 arborescent shapes. Massive : composition granu- 

 lar, individuals very distinct, though small. 



OBSERVATIONS. 



1. This is the pure metal, as produced by nature. It is 

 very fusible, and melts even at the flame of a candle. Be- 

 fore the blowpipe it is volatilized, and leaves a yellow coat- 



