OHDEBVI. HEXAHEDRAL KOUPHONE-SPAR. 



proportion. The fresh fracture of the Greenland variety 

 often presents a beautiful crimson-red tint, which, however, 

 soon fades, the mineral being exposed to light, as has been 

 first observed by Mr ALLAN. 



2. The dodecahedral Kouphone-spar is found in West 

 Greenland, in a bed in mica-slate, from six to twelve feet 

 thick, and is accompanied by several species of the genera 

 Augite-spar and Feld-spar, also by pyramidal Zircon and 

 Eudialyte. It occurs likewise among the minerals ejected 

 by Mount Vesuvius. 



3. HEXAHEDRAL KOUPHONE-SPAR. 



Hexahedral Zeolite, or Analcime. JAM. Syst. Vol. L p. 

 355. Man. p. 142. Analcime. PHILL. p. 129. An- 

 alzim (Cubizit). WERN. Hoffm. H. B. II. 1. S. 251. 

 Analzim. HAUSM. II. S. 586. Analzim. LEONH. 

 S. 458. Analcime. HAUY. Traite', T. III. p. 180. 

 Tabl. comp. p. 51. Traite', 2de Ed. T. III. p. 170. 



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

 Simple forms. H. (P) ; D Vol. I Fig. 31.; 



Ci (o) Vol. I. Fig. 34. Kollefiord, Stromoe, one 



of the Faroe islands. 

 Char, of Comb. Tessular. 

 Combinations. 1. H.Ci. Fassa, Tyrol. Fig. 153. 



2. H. D. Ci.* Vesuvius. 

 Cleavage, hexahedron difficultly obtained ; ano! 



even when distinct, of a very interrupted appear- 



ance-f-. Fracture imperfect conchoidal, uneven. 



* This rare and new variety is preserved in the cabinet of 

 Mr ALLAX. H. 



f I have observed it in some translucent varieties in TVfr 

 ALLAN'S collection ; the transparent ones present more perfect- 

 ly conchoidal fracture. Dr BRE WSTER has found that the crys- 

 tals of this substance are composed in a singular manner" of 



