SMITHSOXITE. 407 xo 63° 45' zb 42° 0' to 64° 24' sa 50 35 zc 52 57 na 61 27 sb 66 6 ta 65 20 nb 35 30 80 48 54 tb 36 55 no 70 42 za 73 5 FIG. 414. V FIG. 416. FIG. 415. K / >■ a Combinations. wv, amc's'.w, amw'els', amw'l's'..e.v'.c', fijnne I'ew'i.f .v.krn, abmsc'l'c'wv’z’x. Twins. Twin-face c. -che faces a striated parallel to their intersections with m. Cleavage, e, m, both easily obtained, the latter very perfect, c, traces. Fracture uneven. Transparent...translucent. Lustre vitreous inclining to adamantine, on a pearly. Colourless, white, grey, yellow, brown, green, blue. Streak white. Brittle. It = 6‘0. g = 3 - 35...3’50. Phosphoresces when rubbed. The crystals aro pyroelectric. The analogous pole being at the end which has any of the hemihedral forms o', e\ u\ w, h’,f, v', q, r', and the antilogous pole at the end which has the hemihedral form s'. In the matrass yields water and turns white. Before the blowpipe on charcoal swells and shines with a green light, nielts with difficulty on the edges. Alone or with soda it de posits a slight sublimate. With solution of cobalt becomes blue, with spots of green. With borax melts into a clear glass Which becomes opaque on cooling. Is soluble in acids, forming ^ jelly of silica. On adding ammonia to the solution a precipi tate falls which is soluble in excess of ammonia. Partially aoluble in potash.
