ELAOLITE. 93 



Lustre vitreous ; that of Pr 4- CD is pearly. Co- 

 lour greenish-grey. Translucent on the edges. 

 Scratches glass. HAUY. Sp. Gr. = 3-4324. HAUY. 



Before the blowpipe it decrepitates most violently, and 

 splits into many small scaly particles, possessing a feeble 

 alcaline reaction. According to VAUQUELIN and CHIL- 

 DREN, it consists of 



Alumina 80-00 76-06. 



Protoxide of Iron 3-00 7'78- 



Water 17'30 14-70. 



BERZELIUS is of opinion that, besides these, it also con- 

 tains some alcaline substance. 

 Its locality is unknown. 



ELAOLITE. 



SPAR. 



Elaolite. JAM. Syst. Vol. II. p. 41. Man. p. 322. Fett- 

 stein. PHILL. p. 136. 



Prismatic. Cleavage, P oo. ?r -f- oo. Less 

 distinct P + QD 112. PHILL. Massive. Frac- 

 ture conchoidal. 



Lustre resinous. Colour duck-blue, passing into 

 blue and green, or brick-red passing into grey 

 and brown. Translucent. If cut, several va- 

 rieties become opalescent. 



Hardness = 5-5 ... 6-0. Sp. Gr. = 2-546 ... 2-618, 

 HOFFMANN. 



Before the blowpipe it melts into a white enamel. Re- 

 duced to powder, it forms a copious gelatine with acids. 

 According to KLAPROTH, it consists of 

 Silica 46-50. 



Alumina 30-25. 



