70 FLINT GENUS. Internally it is almoft always gliftening, feldom lhining. Luftre intermediate between refinous and vi treous: Frafture fine grained uneven, fometimes inclining a litttle to the imperfedlly conchoidal. Fragments indeterminately angular, not particu larly fharp edged. It occurs in fmall, and fine angularly grained, dif- tincl concretions, which fometimes pafs into coarfe grained. More or lefs tranflucenf, the black nearly opaque. Net particularly hard. Eafily frangible. Heavy in a middling degree. Specific gravity 3,757, 3,754, JFerner.^3,668, Karjlen. ' Chemical Characters. It is more eafily melted than the precious garnet.