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Garnet. % It occurs very feldom maffive, more often difiemin- a ted, and in original roundifh grains and finall pieces. It occurs moft commonly cryftallized, and has two Principal cryftallizations, viz. 1. The garnet dodecaedron. 2. The double eight Tided pyramid. a. Garnet dodecaedron. This figure is eiiher perfeft, or more or lefs truncated on all its edges. When thefe truncations increai'e, and caufe the original faces of the dode caedron to difappear, an b. Acute double eight-fided pyramid is formed, in which the lateral planes of the one are fet on the lateral planes of the other, and the fummits are deeply and flatly acumin- fated by four planes, which are conorm- ably-wife fet on the alternate lateral edges. c. 1 he fame figure as the preceding, in which the eight acute angles, formed by the meet ing of the acuminating and lateral planes, and the alternate angles on the common bafis, are truncated. d- Rectangular four-fided prifm, acuminated on both extremities by four planes, which are fet on the lateral edges. I he cryflals are moftly fmall, alfo middle fized, e dom large, and always all around cryftallized. * ace of the cryflals is fometimes fmooth, parti- CUlar, y tne planes of truncation: the planes of acu- n *nation are fometimes diagonally (creaked. Surface thegrains is rough or granulated. K Externally