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MUITE, GIESECKITE, OOSITE, &C. G07 bedded crystals having rounded edges, and massive, at Fahlun in Sweden in chlorite slate. Bonsdorffite.—Cleavage parallel to the faces c of cordierite. Fracture conchoidal. In thin leaves translucent. Lustre waxy. Greenish-brown... olive-green, n = 3-5. Infusible before the blowpipe. Is found in six-sided prisms with cordierite in granite near Abo in Finland. Esmarkitc.—Cleavage parallel to the faces c of cor dierite. Fracture uneven, splintery. Translucent on the edges. Lustre pearly on the cleavage, on the surfaces of fracture vitre ous, inclining to resinous. Green, h = 3-5. g = 2'709. Fusible with difficulty on the edges before the blowpipe. In imbedded crystals having rounded edges, an uneven surface and imperfect terminations. Is found with chlorite imbedded in quartz near Brevig in Norway. Aspasiolite occurs in crystals having the form of cordierite. Green of various shades, some times inclining to brown. II = 3 0. g = 2 764. Infusible before the blowpipe. Is decomposed by boiling hydrochloric acid. Is found in gneiss in the neighbourhood of Kragero in Norway containing portions of colourless or pale violet cordie rite. Pyrargillite.—Fracture uneven. Translucent on the edges., .opaque. Lustre resinous, feeble. Greyish-blue, brown, red. ii = 3'5. G = 2'5. Infusible before the blowpipe. Is completely decomposed by hydrochloric acid. Is found in indistinct imbedded crystals, and massive, in granite at Hel singfors in Finland. Analyses of fahlunite n, o by Trolle Waehtmeister, p of bonsdorffite by v. Bonsdorff, q of esmarkite by Erdmann, r of aspasiolite by Scheerer, s of pyrargillite by Nordenskiold:— n 0 P 1 r s Silica .... 44-96 45-05 46-97 50-90 43-93 Alumina . . . . 36-10 30-70 3006 32-08 32-38 28-93 Protox. iron 3-80 7'22 5-30 3-83 234 5-30 Protox. mangan. . 2-24 1-90 — 0-41 — — Lime .... 1-35 0-96 — Na 1-85 Magnesia . . . 6-76 6-04 9-00 10-32 8-01 2-90 Potash .... 1-38 — — — 1-05 Water .... 935 8-65 10-60 6-49 6-73 16-47 Chlorophyllite occurs in six-sided prisms, with a cleavage perpendicular to the axis of the prism. Green...brownish. Brittle. h = l'5...2'0 on the ends, 11 = 5 on the edges. g = 2'7. Is found at lladdam. Gigantolite occurs in twelve sided prisms having either a cleavage or faces of union sepa rated by films of chlorite perpendicular to the axis of the prism. Lustre on the faces perpendicular to the axis of the prism im perfect metallic. Greenish-grey. Streak white, h = 3-5.