BASALTIC HORNBLENDE. 11 Observations. 1. It is distinguished from the other subspecies of Hornblende by its colour, crystallization, lustre, and easy frangibility. It was confounded with Schorl, until Wer ner pointed out its characters and place in the system. 2. It decomposes more slowly than basalt: hence we frequently find unaltered crystals dispersed through the clay formed by the decomposition of basaltic rocks. 3. Beyer describes a mineral under the name Kohkrt- hornblende, (Coal Hornblende), which appears to be nearly allied to hornblende ; hence it deserves to be no ticed in this part of the system. He describes it in the following terms :—Its colour is velvet-black, passing in to brownish-black It occurs massive and disseminated. The principal fracture is imperfect foliated, almost slaty, sometimes straight, sometimes curved, and inclining to fibrous; the cross fracture is small-grained uneven. The lustre of the principal fracture is shining and glistening, and pearly ; the cross fracture glimmering, or dull. It is opaque. It affords a dark greenish grey-coloured streak. It is soft. It emits a clayey smell when breath ed on. It occurs imbedded in pitchstone-porphyry, be tween Zwickau and Planitz 3. Actynolite. * Vid. Beyer, in CrelPs Chem. Annul. 2. 11. s. 381. Lenz, Tabel. f. 33. Leonhard, Tasch. b. i. s. 267. '
