CHABAZITE. 109 



Composition : silica 54*6, alumina 23*2, soda 14'0, water 

 Kl. Fuses before the blowpipe on charcoal without intu- 

 mescence to a clear glassy globule. Gelatinizes in muriatic 

 acid, with difficulty. 



Dif. ■ Characterized by its crystallization, without cleav 

 age. Distinguished from quartz and leucite by its inferioi 

 hardness ; from calc spar by its fusibility, and by not effer- 

 vescing with acids ; from chabazite and its varieties by fu- 

 sing without intumescence to a glassy globule, and by the 

 crystalline form. 



Obs. Found in amygdaloid and lavas ; also in gneiss. 



Occurs in fine crystallizations in Nova Scotia ; also at 

 Bergen Hill, N. J. ; Perry, Me. ; and in the amygdaloid of 

 the copper region, Lake Superior. The Faroe Ids., Iceland, 

 Vicentine, the Hartz, Sicily, and Vesuvius are some of the 

 foreign localities. 



The name analcime is from the Greek analkis, weak, al- 

 luding to its weak electric power when heated or rubbed. 



CHABAZITE. 



Rhombohedral. Often in rhombohedrons, much resem- 

 bling cubes. (Fig. 1.) R : R = 94^ 46'. Cleavage paral- 

 1 2 3 



lei to the primary faces. Also in complex modifications ol 

 this form, and double six-sided pyramids or short six-sided 

 prisms terminating in truncated pyramids. (Fig. 2.) Also 

 in compound crystals, (fig. 3.) Never massive or fibrous. 



Color white, also yellowish and red. Luster vitreous. 

 Transparent to translucent. H=4 — 4*5. Gr=2*06 — 2*17. 



Composition : silica 48*4, alumina 19*3, lime 8-7, potash 

 2-5, water 21 '1. 



This species includes gmelinite, occurring in small glassy 

 crystals of the form in figure 2 ; also levyne, occurring in 

 compound crystals (fig. 3 ;) also ledererite, which has the form 



Mention some of the distinctive characters of pialcime. • What is 

 id of the crystallization of chabazite? mention other characters. 

 15 



