EARTHS. ADAMANTINE. 58. Adamaminus. 17^ 



ORDER VI. ADAMANTINE. 



Confifiing frhtcipally of corunda or adamantine earth. 



58* ADAMAKTINUS. Confiaing of adamantine 

 earth, the greater part alumina, a little filica and 

 iron : very hard, ponderous, lamellar with ftraight 

 foliations interfeding each other in a 3-fold man- 

 ner, breaking into rhomboidal fragments : per- 

 fedly apyrous, and yielding a little to the file. • 



Corundum, Adamantinus. 



Corunda. Klaproth. Chem, annal. 1789. i. /. 7. 

 Adamantine earth. Kirtjoan mineral, t„ p, ij^ 

 Adamantine fpar, Schmeijer mirtert i. /. 57. 

 Diamond fpar. Jameifon miner, i. ^. 93, 

 Imperfeft Corundum. Ibomfon chem. '^. p. i^oj. 



Found in Chinat Bombay y Francey and Spaing in granite : colouif 

 grey, with often various Ihades of green, blue and brown: 

 luftre tranfparent, and when polifhed Ihines like mother of 

 pearl ; is fonietimes found maffive, but moil commonly in 6- 

 fided prifms, and fimple acute 6Hded truncated pyramids ; 

 it is uied like diamond powder for cutting and polilhing hard 

 minerals: fpecific gravity 3,981. contains corunda and alu- 

 mina 84,00. filica 6,50, oxyde of iroi^ 7,50. Klaproth. 



