CINNABAR, the κwvαβαpις of Theophrastus, is the native sulphide of mercury, and the only commercial source of that metal and its compounds. It crystallizes in the rhombohedral form, in which condition it is sometimes found; but generally it occurs in fibrous or amorphous masses bedded in slate rocks and shales, and more rarely in veins in granitic or porphyritic rocks. In hardness it is intermediate between gypsum and calcspar; its specific gravity is 8 ’ 998, and its colour varies from a fine bright red to a reddish-brown and leaden-grey hue. It possesses the same composition as the ordinary vermilion of commerce for which it may, when pure and fine in colour, sometimes be used after simple lévigation, although the greater part of that brilliant pigment is artificially prepared. Pure cinnabar should contain 86 ’ 21 per cent, of mercury, combined with 13*79 of sulphur; but in its native state the ore is frequently contaminated with oxide of iron, clay, and bituminous matter. The principal European localities for cinnabar are at Idria in Carniola, and at Almaden in Spain, whence the British demand is mainly supplied. It is also extensively worked at New Almaden and several other localities in California, in the southern part of Peru, and in Borneo, Japan, and China. See Vermilion.