386 BITUMINOUS FAMILY. Fourth Subspecies. Foliated Coal. Blatterkohle, Werner. Id. Estner, b. Hi. s. 155.—Le Charbon lamelleux, Brock, t. ii. p. 54.—Blatterkohle, Rems, b. iii. s. 128. Id. Voigt, s. 72. Id. Lud. b. i. s. 189. Id. Suck. 2ter th. s. 52. Id. Bert. s. 347. Id. Mohs, b. ii. s. 347. Id. Leonhard, Tabel. s. 50. Id. Karslen, Tabel. s. 58. Id, Lem, b. ii. s. 106'9. External Characters. Its colour is intermediate between velvet-black and greyish-black; sometimes it has a pavonine tarnish on the fracture. It occurs massive. The principal fracture is splendent ;• the cross fracture is glistening, and the lustre is resinous. The principal or longitudinal fracture is straight fo liated, with a single cleavage, which is more or less per fect ; the cross fracture is slaty. The fragments are indeterminate angular, approaching to cubical. It is soft and very soft. It is intermediate between brittle and sectilc. It is very easily frangible. It is light. Geognostic Situation. It occurs in the coal formation. Geographic Situation. It is found in the Electorate of Saxony, and in Silesia- Fifth
