OBDERXI. PRISMATIC BISMUTH-GLANCE. 19 



2. It is generally found imbedded in several rocks, parti- 

 cularly in granite, and is not unfrequently met with in se- 

 veral repositories of pyramidal Tin-ore. Besides this species, 

 it is most commonly accompanied by rhombohedral Quartz 

 and prismatic Scheelium-ore. 



3. Among the oldest known localities of the present spe- 

 cies are Altenberg in Saxony, and Schlaggenwald and Zinn- 

 wald in Bohemia. As in these places, it occurs also in 

 Cornwall, along with pyramidal Tin-ore. In Norway and 

 Sweden it occurs imbedded in zircon^syenite and granite ; 

 in granite also, at Carrock in Cumberland, and in West- 

 moreland in England, at Loch Creran in Scotland, &c. It 

 is frequent in the granite and gneiss of the United States 

 of North America, and has been found also in the valley 

 of Chamouni in Savoy, and in Silesia. 



GENUS VI. BISMUTH-GLANCE. 

 1. PRISMATIC BISMUTH-GLANCE, 



Prismatic Bismuth-Glance. JAM. Syst Vol. III. p. 384. 

 Man. p. 283. Sulphuret of Bismuth. PHILL. p. 273* 

 Wismuthglanz. WERX. Hoffm. H. B. IV. L S. G8. 

 Wismuthglanz. HAUSM. I. S. 190. Wisrauthglanz. 

 LEOXH. S. 213. Bismuth sulfure. HAUY. Traite', 

 T. IV. p. 190. Tabl. comp. p. 105. ^fiwte, 2de Ed. 

 T. IV. p. 210. 



Fundamental form. Scalene four-sided pyramid 

 of unknown dimensions. Vol. I. Fig. 9. 



Simple forms and combinations not determined. 



Cleavage, imperfect in the direction of P -f- o& y 

 which is nearly equal to 90 ; with great perfec- 

 tion parallel to one of the diagonals, less distinct- 

 ly parallel to the other ; P oo imperfect. 

 Fracture scarcely observable. Surface of the 

 prisms deeply streaked parallel to the axis. 



