i6o £ARTHS. siliceous. 53, 54. 



13. CHLOROGRANATUS. Confiding of filica, 

 a large proportion of oxyde of iron, and car- 

 bonate of lime, Vv'ith frequently alumina : hard, 

 never opake or fubopake, cryflallized : eafily 

 fufible in the fire. 



• ■ 



werus* Greerf, becomhig honey-yellow in a white heat. 

 Weigkb. Chem^ annaU 1788. i.p.206. 



1. In doable S-fided pyramids, augmented at each p»int by' 



another 3-rided pyramid. 



2, In 6-rided, prifras, terminating each fide in a 3-iided py- 



ramid. 



Found in Bohemia near Lichfe'ivalledein, in Saxony near Ehrerf^ 

 frisderfdorfy Breitenbrunn^ Eibenflock, and Schnjoartzenburg, 

 and in Franconia near llmenau on mount Ehrenburg: co- 

 lour from leek to olive-green, fometimes diaphanous, fome- 

 times pellucid, and often forms entire ftrata with layers of 

 clay : frequently contains a fourth part of iron, and is ufed 

 as a fiux in iron furnaces : fpecific gravity from 3754. to 



3757- 



duhius. Red, cubic* 



Weftrumb Chem, annaU 1789. 2. p. 26, &:c. 



Found contains about a fifth part of carbonate of lime 



impregnated with carbonic acid gas, and about a tenth part 

 of iron : cryllals fmall, aggregate, feated on friable fand- 

 rtone : may probably not belong to this genus. 



54. ARENA. Confifl-ing of comminuted filiceous 

 flones : rough, hard, dry, in minute difl:in6b 

 granulations, not penetrable by water: not fu- 

 fible per fe, but melting v/ith foda into glafs. 



Sand. 



A. Originating from comminuted Flint-Jiones, 



tilicea» Compofed of fragments of fiint. 



Arena filicea. Syjl. nat,x\\, "^^ p. 199. ». 14, 

 Found in Buckingbamjhirt and other places, 



