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Sihceous Genus. Luflre, 3; but, as they are commonly in a ltate 01 decompofition, o. Tranfparency, wfien frefh, 3.2; but generally from decompofition, o. Fradturefoiiatcd, inclining to conchoidal. Hardnefs when intire, frorn 8 to 9; when mouldering, 5 or 6. Sp. gr. 2,4648. Fufible per Je by'the blovvpipe, but difficultly Mineral alkali fcarcely fluxes thern, borax and microcofinic falt, very flowly. Mi. Bergman found them to contain 0,53 filex, °>39 ar g'dl, and 0,06 lrme, butnoiron, orfcarce any. 3 Bergm. p, 206. The decompofed ftate of this flone does not proceed merely from the a&ion of the air, nor expofure tofulphureous vapours, bnt principallv from the heat to which it was expofcd ; for it. is found opake, and mouldering even in the midft of fohd malles of iava, as. Mr. Werner has ob* ferved. 4 Helvet. Magaz. p. 241. ' 2jth Species. Shorlite *. Shorlartiger Beryll of Werner’s Mine ral Syltem. Stangenftein of Lelke. Its colour, greenifh white, fometimes inclining to yellowilh, or fulphur yellow. Moftly found in irregulär oblong mafles or co- lumns, inferted in a mixture of quartz and mica, or granite. Mr. La Peyroufe-teils us, he * Werner’s Cronft. p. ,69. Weißen Hangen fliorl. 1 Chy. Ann. 1788, p. 330. 6 found