2) PHYSIOGRAPHY. CLASS II. 



11. AXOTOMOUS KOUPHONE-SPAR. 



Axifrangible Zeolite or Apophyllite (in part). JAM. Syst. 

 Vol. I. p. 384. Man. p. 151. Apophyllit. PHII.L. p. 

 HO. Ichtbyophthalm. WEBN. Hoifm. H. B. II. 1. 

 S. 357- Apophyllit. HAUSM. II. S. 580. Apophyllit 

 (in part). LEONI?. S. 590. Apophyllite (in part). HAUY. 

 Tabl. comp. p. 36. Traite, 2de Ed. T. III. p. 191. 



Fundamental form. Scalene four-sided pyramid. 

 P = 106 52', 101 37', 120 34'. Vol. I. Fig. 9. 

 HAUY. 



a : b : c = 1 : V 0-6923 : V 0-6154. 



Simple forms. P oo (P), P (r) ; Pr + oo (M) ; 

 Pr + </> (T). One of the combinations gene- 

 rally quoted is represented Fig. 11. 



Cleavage, P oo highly perfect, traces of Pr -f oo 

 and Pr + oo. Fracture uneven, imperfect con- 

 choidal. Surface, Pr + oo and Pr + oo faintly 

 streaked in a vertical direction, P oo parallel 

 to the edges of combination with P. 



Lustre vitreous. It is pearly upon P oc, both 

 upon faces of crystallisation and of cleavage. 

 Colour, several shades of white. Streak white. 

 Transparent ... translucent. 



Brittle. Hardness = 4*5 ... 5-0. Sp. Gr. 2467, 

 HAUY, 



OBSERVATIONS. 



1. The forms quoted in the above description were for- 

 merly given by HAUY for the variety of Apophyllite from 

 Fassa in the Tyrol, but have since been abandoned by 

 him in the second edition of his Traite, where he united 

 all the varieties within a single species, having pyramidal 

 forms. Dr BREWSTER has observed, that in certain va- 



