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WOLLASTONITE. 289 Twins. Twin-face c. Cleavage, c, t, u, a, a being the brightest. Fracture uneven. Semi-transparent...translucent on the edges. Lustre vitreous, inclining to pearly on the cleavages. White, passing into grey, yellow, red, and brown. Streak white. Itather brittle. II = 6'0. o = 2'8.. ,2'0. Melts with difficulty before the blowpipe into a semi-transpa rent glass. Is soluble in borax and salt of phosphorus, leaving a skeleton of silica. Is completely decomposed by hydrochloric acid, leaving a jelly of silica. CaSi, silica 52'37, lime 47'63. Analyses of wollastonite a from Skriibbole in Finland by Bonsdorff, b from Perhoniemi in Finland by II. Bose, c from Cziklowa by Stromeyer, A by Beudant, e from Wilsborough on Lake Champlain by Seybert, f by Vanuxem :— a b c d e / Silica .... 52-58 62-19 61-45 63-1 51-0 61-07 1 nine .... 44-45 40-93 47-41 451 40-0 47’00 Magnesia . . . 0-08 (M» 0 20) 1-8 trace ■— Bed oxide of iron 0-13 (i'e 0-40) — 13 1-35 Water .... 099 — 0-08 — l-o •— Analyses of wollastonitc g from Capo di Bove by v. Kobell, 7( from Diana in New York by Beck, i from Pargas by Palander, k from Gockum in Upland by Weidling, I from Ilarzburg by Bammelsberg, m from Greenville in Upper Canada by Bunce:— q h i k I m Silica 61-50 61-90 50-00 52-16 63 01 63'05 Lime 46-15 47-65 47'21 45-04 44-91 45'74 Magnesia .... 0-65 Aile O'li 0-90 i"04 — Bed oxide of iron . — 0-25 — o - 87 i'e l - 20 Water 200 — (m» 0’3l) 1’59 — Occurs in attached and imbedded crystals, lamellar, granular or columnar masses, usually in beds of granular limestone in the older slate rocks, with garnet, pyroxene and amphibole. Is found at Cziklowa and Orawitza in the Banat, Skrabbole, Pargas, and Porhoniemi in Finland, at Gdkum in Sweden, crys tallized in the Fossa Grande in matter ejected by Vesuvius, and at Capo di Bove near Borne in lava, at Greenville in Canada, in the United States, in Wilsborough in New York, Bucks County and Easton in Pennsylvania, in Hesse Darmstadt, Auerbach near Schwarzenberg in Saxony, in Ceylon with garnet in gneiss, in the castle rock of Edinburgh in trap. A clcavable substance resembling wollastonite in appearance and composition has been found in the slags of iron furnaces. o