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EPIDOTE. 307 is yellow whilst hot and colourless cold. With nitrate of cobalt becomes deep grey, approaching to black. Analyses of zoiste from the Saualp in Carinthia a crystal lized, b massive, both by Klaproth, c from the Fichte]gebirge by Bucholz, d from the Fichtelgebirge by Geffken, e from Williamsburgh by Thomson, f from Faltigl (a = 3'28) by Her mann :— a b c d e f Silica 45 44'0 40'25 40'03 40'21 40’95 Alumina .... 29 32'0 30’25 29 83 25-59 30’34 Bed OX. iron ... 3 2 5 4-50 Ee 4-24 7 68 4'90 Protox. mangan. . . — — — 7 - 55 — c 1-13 Bime 21 20‘0 22-50 18-85 23'28 21‘56 Water — — 2-00 — l - 7l 0'6G Is found in attached crystals on the Saualp in Carinthia, Sterzing in the Tyrol, Femleite in Fusch in Salzburg, Baireuth, Conradsreuth near Hof in Bavaria, the Ural. It is doubtful whether the analyses c, d, e, f refer to zoisite or to epidote, with which, as we afterwards state, it has been confounded. In October, 1831, Mr. Brooke gave an account of the crystalline form of this mineral, by which its form appears to approach very nearly to that of euclase, if not to be identical with it. Zoisite is usually considered to be a variety of epidote, mid the distinction between the two substances is generally described as one of colour only, yet they have not any corre sponding cleavages, faces, or angles. For it will be found that the crystals of epidote are invariably lengthened in the direction a perpendicular to the face b, while those of zoisite are as invariably lengthened in the direction of the edge kk'. The priucipal cleavage of zoisite is parallel to the face b, correspond ing to that of euclase, while the principal cleavages of epidote nre perpendicular to the face b. The distinction between the two substances is therefore so strongly marked as to lead to the conclusion that they have not been examined and compared by any of tho authors who rest the distinction between them chiefly on the difference of colour. 172. EPIDOTE. — Epidote ; Phillips, Hauy. Prismatoi- diseher Augit-Spath ; Mobs. Epidot; Hausmann, Haidinger. Oblique. 101,100=63° 43'; 111,010 = 35° 10'-5 ; 101,001 =51° 4l'. 100, b 010, t 001, Z Oil, U 012, i 201, « 302, r 101,