452 TALC GENUS. Externally and internally its luftre is fhining and fplendent, and is completely pearly. Its fradture is very broad, diverging, promifcuous, a little curved radiated, and fometimes paffes into curved foliated. The fradture of the cryftals is foliated, and prefents a three fold cleavage, in which the folia interfedl each other obliquely, and under unequal angles; but of thefe only one cleavage is diftincL Fragments flaty, fplintery, wedge-fhaped, and fome times imperfedtly rhomboidal. It occurs in wedge-lhaped diftindt concretions, which are often very promifcuous, and then pafs into large and coarfe grained diftindt concretions. Ufually tranflucent, and the cryftals often tranfp 3 ' rent< Soft. Not particularly brittle, approaching to mild. Has a flight degree of flexibility. Eafily frangible. Feels a little greafy ? Not particularly heavy, approaching to heavy. Specific gravity—3,517, Saujfure the younger.—3,6 2 ' f Hermann. , , Chemical Character. Before the blow pipe it is infuflble without addi* tion. Const¥ s,it