ORDER XI. HEXAHED11AL SILVER-CLANCE. H 



other countries. The foliated variety is found in Corn- 

 wall, in the Bannat, in Siegen, and in Mansfeld. 

 5. It is a rich and highly valuable ore of copper. 



GENUS II. SILVER-GLANCE, 

 1. HEXAHEDRAL SILVER-GLANCE. 



Hexahedral Silver-Glance. JAM. Syst. Vol. III. p. 338. 

 Man. p. 279. Sulphuret of Silver. Vitreous Silver. 

 PHILL. f>, 288. Glaserz. WEBN. Hoffm. H. B. III. 

 2. S. 57. Glanzerz. HAUSM. I. S. 136. Silberglanz. 

 LEONH. S. 169. Argent sulfure'. HAUY. T. III. p. 

 398. TabL comp. p. 74. Traits', 2de Ed. T. III. p. 265. 



Fundamental form. Hexahedron. Vol. I. Fig. 1. 



Simple forms. H (r) Himmelsfurst, Freiberg ; O 



(/i) Vol. I. Fig. 2., Joachiinsthal, Bohemia ; D 



(*), Vol. I. Fig. 31., Himmelsfurst; Ci (o) 

 Vol. I. Fig. 34., Morgenstern mine, Freiberg. 



Char, of Comb. Tessular. 



Combinations. 1. H. O. Vol. I. Fig. 3. and 4. 

 2. H. D. Fig. 151. 3. H. Ci. Fig. 153. 4. H. 

 O. D. Ci. All of them from the mines near 

 Freiberg. 



Cleavage, sometimes traces parallel to the dodeca- 

 hedron. Fracture imperfect and small conchoi- 

 dal, uneven. Surface, nearly of the same de- 

 scription in all the forms, often uneven, and pos- 

 sessing low degrees of lustre. Subject to tarnish. 



Lustre metallic. Colour blackish lead-grey. Streak 

 shining. 



Malleable. Hardness = 20 ... 2-5. Sp. Gr. = 

 7-196, crystals from Freiberg. 



