MAGNETITE. 259 Cleavage, a, o both very imperfect. Fracture conchoidal. Opaque. Lustre metallic. Iron-black. Streak dark brown. Brittle, n = 6 - o...6'5. G = 6'07...6‘13. Slightly magnetic, without sensible polarity. Infusible before the blowpipe. "With soda on charcoal in the inner flame yields a sublimate of oxide of zinc. In the outer flame imparts a purple colour to glass of borax. Completely soluble in warm hydrochloric acid, forming a yellowish-green solution. E44-, where b is protoxide of iron Ee, protoxide of manganese Mu and oxide of zinc zn, and b is red oxide of iron le and oxide of manganese Sn. Analyses of Franklinite by Berthier and Abich :— Bed oxide of iron . . 66'0 68'88 Oxide of manganese . l6 - o 18'17 Oxide of zinc .... 17'0 10‘81 Alumina — 0'73 Silica — 0'40 In imbedded crystals, angular or rounded grains, and granular masses. Is found in crystals imbedded in spartalite, and in rounded grains imbedded in calcite, at Franklin and Sterling in New Jersey, with calamine and sinithsonito at Altenberg near Aix la Chapelle. 13G. MAGNETITE.—Magnetic iron ore ; Phillips. Fer oxidule; Hauy. Oktaedrisches Eisen-Erz; Mohs. Magnet- eisenstein ; Hausmann. Magnetit; Haidinger. Cubic. a loo, d 011, 0 111, 10 1 1, z 16 1 1. aa' 90° 0' mo dd' 60 0 sa da 45 0 sa’ 00 70 32 ft sa oa 64 44 so ea 26 34 sd" pa 70 32 ya pa 48 11 yo pd 19 28 za ma 26 14 zo 210, p 122, m 311, s 321, 29° so' EIG. 284. 36 42 64 41 74 30 22 13 19 6 8 3 46 41 6 3 49 41
