OLIVINE. 73 Geognostic Situation. It occurs imbedded iri basalt, greenstone, porphyry, and lava, and generally accompanied with augite. Geographic Situation. Europe.—It occurs in the flcetz-trap rocks of the Lo- thians, and other districts in Scotland; and in those of the Hebrides. Sparingly in the flcetz-trap rocks iri the north of Ireland *. It is found in Iceland ; and on the Continent, in Bohemia, Saxony, Stiria, Austria, Hun gary, France, Italy, Spain, &c. Africa.—Teneriffe; St Helena; Isle de Bourbon. America.—Greenland; and the Cordilleras of South America. Observations. i. a. This mineral was first established as a distinct species by Werner: before his time, it had been con founded with Chrysolite. Ilauy is still of opinion, that it is but a variety of chrysolite ; but the following com parison of the characters of the two minerals, shew that they may be viewed as different species:—The colours t>f olivine do not agree with those of chrysolite: the most common external shape of olivine is granular, whereas that of chrysolite is angular and notched; the rolled pieces of olivine have not a scaly and splintery surface, as is the case with chrysolite: olivine is seldom crystal lised, and when it is so, the crystai-suite is inconsider able, whereas chrysolite is frequently crystallised, and its forms very various; the lateral planes of the crystals of olivine * Orcenough*