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558 CHE01IATES. FIG. 653. FIG. 654. FIG. 555. Combinations. bx, mt.l.u.s.a, mtc..v.z.y.b, tkmf.M.b.d, ntvmdb, tzykvumfba, mtf..x.e.c.d.s, mtfxb..c.a.s, mtxfck..v.d,z.s, mt- xf.sak.yz, mtxfyzsakvu, mtxfcdglyzw. The faces a, b, m,f, g, d striated parallel to their intersections with each other; I, usually curved. Cleavage, m, tolerably distinct; a, c, less distinct. All imperfect. Fracture small conchoidal, uneven. Translucent...translucent on the edges. Lustre adamantine, n = 2'974, 2'600. Hyacinth-red of various shades. Streak orange. Sectile. ii = 2 - 5...3'0. G = 6-9...e-i. Decrepitates when heated. Before the blowpipe on charcoal grows darker and melts, a portion of the lead being reduced. With borax or salt of phosphorus fuses easily in the outer flame into a green glass, and in the inner flame into a grey glass. With soda the lead is easily reduced. Is decomposed by warm hydrochloric acid, leaving a crystalline powder of chloride of lead. The solution is green. Nitric acid affords, with difficulty, a reddish-yellow solution. In potash becomes brown and dissolves, forming a yellow solution. PbCr, chromic acid 32-60, oxide of lead 67 - 50. Analyses by Pfaff and Berzelius:— Chromic acid 31-72 3l - 60 Oxide of lead 87'9l 68 50 Is found in crystals, massive and disseminated, in veins of quartz in granite, in the gold mines of Beresowsk in Siberia; in