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56 CHRYSOLITE FAMILY. concretions. It is opaque. This subspecies has hitherto' been found only at Arendal in Norway. (2.) Foliated Augite.—Colour passes from velvet-black through greenish-black, into blackish-green, and some times approaches dark leek-green. Occurs only crystal-* lised, and its crystallizations are nearly the same with those of the granular subspecies. Internally shining, approaching to splendent, and the lustre intermediate between resinous and vitreous. Principal fracture per fect foliated, with a double slightly oblique angular cleav age, parallel with the smaller lateral planes of the six- sided prism ; also a third cleavage, parallel with the truncations on the acuter edges of the six-sided prism. Cross fracture conchoidal. It is sometimes opaque, some times translucent on the edges : the crystals which occur in the basalt of Bohemia, in general belong to this sub species; also those from Frascati, Etna, and Vesuvius. (3 ) Conchoidal Augite—Colour greenish-black, pass ing into blackish-green; also into a very rare dark olive- green, sometimes even into liver-brown. Occurs in im bedded grains. Lustre splendent, and intermediate be tween resinous and vitreous. Fracture imperfect, but flat conchoidal. Translucent on the edges, or translu cent. It occurs only in the tloetz-trap formation, and is the rarest of the four subspecies. It occurs in the basalt of Fulda, and near Cassel in Ilessia. (4.) Common Augite.—Colour blackish-green, and vel vet-black. Occurs in large and small imbedded grains. Internally intermediate between shining and glistening, and lustre resinous. Fracture coarse and small grained uneven. Translucent on the edges, seldom translucent. Occurs in the floetz-trap formation. 3. Steffens, in his Handbuch, describes a species un der the name Keraphyllite, which Karsten and Werner refer
