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26 RUBY FAMILY. 2. Ceylanite. • ■ Zeylanit, Werner. Schorl ou Gienat brun, Rome de Lisle, t. iii. p. 180. Note 21. —Ceylanit, La Metherie, Journ. de Phys. 1793, p. 23.— PJeonaste, Hauy, t. iii. p. 17- Id. Broch. t. ii. p. 525.— Ceylanite, Reuss, b. ii. th. ii. s. 38. Id. I.Aid. b. ii. s. 148. Id. Suckorv, l r th. s. 148.—Pleonast, Bertele, s. 284. Id. Molts, b. i. s. 100. Id. Lucas, p. 52. 263.—Spinelle pleo- naste, Brong. t. i. p. 438. Id. Steffens, b. i. S. 27. External Characters. Its colour is muddy duck-blue, and greyish-black, which approaches to iron-black. It occurs in blunt angular pieces, and grains; and crystallised in the following figures: 1. Octahedron, either perfect, or truncated on the edges. Figs. 9, and 10. 2. Octahedron, having each of its angles acuminated by four planes, which are set on the lateral planes. Fig. 11. 3. Garnet or rhomboidal dodecahedron. Fig. 12. The crystals are small, and very small, seldom middle- sized ; and sometimes imbedded, sometimes superimposed. Externally the angular pieces and grains are rough and glimmering, or glistening, but the crystals are smooth and splendent. Internally it is splendent, and the lustre is resinous, inclining to semi-metallic. The fracture is perfect, and rather flat conchoidal. The fragments are angular, and very sharp-edged. It is translucent on the edges. It is hard: scratches quartz, but not so readily as spinel. It is rather easily frangible. It