398 GRAPHITE FAMILV. Specific gravity, (but uncertain Whether of scaly of compact graphite), Kirwan, 1.987 2.267 Brisson, 2.1.500 2.456 Hany, 2.0891 2.2456 Second Subspecies. , Compact Graphite. JDichter Graphit, Werner. Graphite gramileux, Brong. t.ii. p. 54.—Dichter Graphit, Ear. sten, Tabel. s. 58. Id. Haus. s. 115. Id. Lenz, b. ii. s. 1085. External Characters. The colour is nearly the same with the preceding, onlv rather blacker. It occurs massive, and disseminated. Internally it is glimmering, sometimes glistening and the lustre is metallic. ' ° The fracture is fine-grained uneven, which passes into even % and also into large and flat conchoidal. Some varieties shew a slaty longitudinal fracture. It occurs in columnar distinct concretions. In other characters it agrees with the preceding sub species. Chemical Characters. When heated in a furnace, it burns, and during com bustion emits a great deal of carbonic acid, and leaves a residuum of red oxide of iron. Constituent
