MEIONITE, 



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lar spar is more fibrous in the appearance of the surface, 

 and is less hard ; it is also phosphorescent, and gelatinizes 

 with acids. 



Obs. Found mostly in the older crystalline rocks, and 

 also in some volcanic rocks* It is especially common in 

 granular limestone. Fine crystals occur at Gouverneur, N# 

 Y., and at Two ponds and Amity, N. Y. ; at Bolton, 

 Boxborough and Littleton, Mass. ; at Franklin and Newton, 

 N.J. It occurs massive at Marlboro', Vt. ; Westfield, Mass. ; 

 .Monroe, Ct. Foreign localities are at Arendal, Norway; 

 Warmland, .Sweden ; Pargas in Finland, and also at Vesu- 

 vius, whence comes the small crystals called meionite. 



Nuttdllite, Wernerite, and Glaucolite are varieties of this species. 



Dipyre from the Pyrenees, occurring in four or eight-sided prisms, has 

 also been considered one of its varieties. It however contains silica 

 555, alumina 24 - 8, lime 96, with 9*4 per cent, of soda, and is more 

 allied in composition to the feldspars. Sp. gr.=265. Occurs with talc 

 and chlorite. 



MEIONITE. 



Dimetric. In small glassy square prisms, terminating in 

 pyramids, and resembling scapolite ; e : e=sl36° 11'. Cleav- 

 age rather perfect, parallel with M and e. 



Colorless or white, and transparent to translucent. H=s 

 5-5—6. Gr=2.5— 2*75. 



Composition: silica 42*1, alumina 31*9, lime 26*0. Be- 

 fore the blowpipe yields a colorless glass. 



Dif. Differs from scapolite in the angle of the summit 

 and in composition , from the zeolites in being anhydrous. 



Obs. Found at Mt. Somma, near Naples, in small crys- 

 tals in geodes in lava. 



Mizzonite is closely similar. It has for the angle c : e= 

 135° 56', (Scacchi.) 



Sarcolite. Dimetric. Resembling somewhat analcime in appear- 

 ance, being flesh-red to reddish white. Extremely brittle. Gelatinizes 

 with acids. Of rare occurrence at Mt. Somma. 



Gehlenite. Crystals square prisms like meionite : color gray ; nearly 

 opaque. H=5'5 — 6. Gr=29— 3'1. Composition, silica 29"6, alum- 

 ina 248, lime 35*3, protoxyd of iron 6*6, water 33. Infusible. With 



In what rocks does it occur 1 Mention the characters of spodumene 

 How much lithia does it contain ] How does it differ from feldspar and 

 scapolite 1 



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