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296 SILICATES. Before the blowpipe melts readily into a grey and green enamel. Is not acted upon by acids. Analyses of diallage a from the Baste (mean of two), b from Sa 7miHO /I ftinvn i 1 m. 11 1 -rr ..i i » « Silica .... Alumina . . Magnesia . . Lime . . . Protoxide of iron Protox. mang.. Water . . . } t, both by Begnault, f from Grossarl in a b C d e / 52-89 51-34 63-20 51-25 60-05 60-20 2-70 4-39 2-47 3-98 2-58 3-80 17-88 16-09 14-91 22-88 17-24 10-40 17-40 18'28 19-09 11-18 15-03 20-20 • 8-41 8-23 8-07 0-75 11-98 8-40 0-38 — — traces 1-06 2-11 1-77 3-32 2-13 — In imperfect crystals; massive having a crystalline structure: granular; lamellar. Is found with amphibole in euphotide in the Harzburo- I orest m the Harz, and la Prese in the Yalteline; in Silesia, in the Apennines, in the Ural. ,. Liaclasite appears to he a variety of diallage from the eupho tide ot the Harzburg Forest, and the gneiss of the G-uadarrama mountains in Spain, in crystals showing the faces a, b, m, s. Between bronze and brass-yellow, more or less inclining to green. Streak greenish-grey, h = 3-6...40. g = 3-064. Ac cording to Kohler, diaelasite from the Harzburg Forest con tains silica 63-74, alumina 1-34, magnesia 26-09, lime 4 73, protoxide of iron 11-51, protoxide of manganese 0-23, water 3-70.' ®^-0-D0NITE. — Siliciferous oxide of manganese ; Phillips. Manganese oxide silicifere; Hauy. Diatomer Au- git-Spath ; Mohs. Bhodonit; Hausmann, Haidinger. Oblique. Isomorphous with augite. a 100, b 010, c 001, m 110, all cleavages. ac 74° o' be 90 0 ma 43 33 ba 90 0 mm 87 6 Cleavage, a, perfect; b, less perfect; m, imperfect. Frac ture uneven Translucent...translucent on the edges. Lustre vi reous, inclining to pearly on the cleavages m. Itose-red,
