COMMON DOLOMITE. 91 It is faintly translucent, or only translucent on the edges. It is semi-hard, sometimes approaching to soft. It is brittle. It feels rough and meagre. It is easily frangible. Specific gravity, Dolomite of Alps of Carinthia, 2.S35, Klaproth. It effervesces very feebly with acids,—a character that distinguishes it from granular limestone, which effervesce* briskly. It in general phosphoresces when placed on heated iron, or when rubbed in the dark ; and this property is much stronger in some varieties than in others. Chemical and Physical Characters. Constituent Parts. St Gothard. Apennines. Carinthia. Antique. Carbonate of Magnesia, Carbonate of Lime, Oxide of Manganese, Oxide of Iron, 40.50 35.00 48.00 48.00 42.00 05.00 52.00 51.59 0.25 0.50 0.75 0.20 I.08S, 100 Klaproth, Beit. b. iv. «. 209. Klaproth, Id. s. 214. 100 100.20 99-59 Klaproth, Klaproth. Id. s. 219. Id. s. 222. Iona. Carbonic Acid, Lime, Magnesia, Insoluble Matter, 48.00 31.12 17.08 4.00 Tennant, Phil. Trans, for 1799. Geognostic