ye ZIRCON GENUS. fometimes uneven and fometimes rough, and is gliftening. Internally its lurtre is ftrongly fplendent, and re- finous, paffing into adamantine. Frad:ure perfectly fmall conehoidal. Fragments indeterminately angular, fharp-edged. It is intermediate between tranfparent and femi- tranfparent, and approaches fometimes more to the one fometimes more to the other, and is duplicating tranfparent *. 6 Hard in a high degree, very little aifeded by the file ’f. 3 Brittle. Not particularly difficultly frangible. Heavy. SpeciJc g„vi t7 _ 4 ,,„o, HW._ 4 ,6, 5i 4,6666, Karjlen. Constituent Parts. Zirconia, 69,0 Silica 26,50 Qxyd of iron, 0,50 96,0 Klaproth, b. 1. f 222'. * Hauy. f Eftner. Chemical
