C 390 ) III. GRAPHITE FAMILY. Tins Family contains three species, viz. Glance-Coal, Graphite, and Mineral Charcoal. I. Glance-Coal. Glanzkohle, Werner. This species contains three subspecies, viz. Conchoidal Glance-Coal, Slaty Glance-Coal, and Columnar Glance- Coal. First Subspecies. Conchoidal Glance-Coal. Muschliche Glanzkohle, Werner. Id. Ksiner, b iii. s. 135—I,a Houille eclatant, ou le Glanzkohle, Brock■ t. ii. p. 50.—Glanzkohle, Reuss, b. iii. s. 138. Id. Voigt, s. 90. Id. Reonhurd, Tabel. s, 49—Scldagiger Anthra- cit, Karsicn, Tabel. s. 58. Id. Ilaus. s. 115—Muschlicher Anthracite, Lenz, b. ii. s. 1077. ' External Characters. Its colour is iron-black, of various degrees of intensity* which rather inclines to brown; and on the surface it has a tempered-steel coloured tarnish. It occurs massive and vesicular; the interior of the vesicles has a tempered-steel coloured tarnish. Internally