Cinnabar. Also called cinnabar nativum, minium purum, minium Graecorum, (magnes epilepsiae, from its supposed usefulness in epilepsies,) alzemqfor, ammion, azamar. Vitruvius calls it anthrax. Mineralogie de Haiiy iii. 437.

Native cinnabar, a ponderous, red, sulphureous ore of quicksilver. It is found in Spain, Hungary, the East Indies, etc. The finest is brought from the East Indies. It is found sometimes in veins, occasionally in grains, or crystallized. Its crystals are tetraedrous.

Sometimes it is brought to us in a large irregular mass; at others in smaller roundish ones, smooth without, and striated within; and of a bright red colour throughout; its streak red and metallic; and its specific gravity from 5.419 to 10.1285. It is insoluble in the nitric, and soluble in the muriatic acid.

This ore consists of sulphur and quicksilver; the liner the colour, the more quicksilver it contains: with these constituents there is generally much earthy matter, from which it is easily sublimed. M. Proust, in the Journal de Physique, vol. liii. has shown that the mercury is in the proportion of 85 to 15 of sulphur, in 100 parts. The mercury seems, however, to be in a metallic state, since, on distilling a mixture of muriat of mercury and sulphur, the product is oxy-muriat of mercury and cinnabar. AEthiops mineral, according to Berthollet, differs only from cinnabar by its containing sulphurated hydrogen. See Argentum vivum. See Dict, of Chemistry, Lewis's Mat. Med. Neumann's Chem. Works.

Cinnabar is a name now confined to the native and factitious sort; but formerly it was applied to dragon's blood, madder root, ceruss calcined to redness, and to some other articles.

Artificial cinnabar, hydrargyrus sulphuratus ruber, is prepared by mixing purified quicksilver forty ounces, and pure sulphur eight ounces. The quicksilver must be stirred into the sulphur melted; and if the mixture takes fire, it is to be extinguished by covering the vessel. Then let the matter be reduced to powder and sublimed. Ph. Lond. 1788.

The quicksilver in the cinnabars is rendered inert by the sulphur, and of no efficacy as an internal medicine. The factitious or native cinnabar is supposed never to be active without having lost a portion of its sulphur, though it has been esteemed an useful medicine in diseases of the skin, in arthritic, rheumatic, and epileptic cases. Its chief use is for fumigating venereal ulcers; when the quicksilver is resolved into vapour, and blends in part with a volatile vitriolic acid, derived from the sulphur, forming a mercurial salt. This method is useful when a rapid effect is to be produced; but in general the salivation excited is violent and profuse, so that this remedy has been lately neglected.

If adulterated with red lead, it may be discovered by putting a little on a hot iron, for the cinnabar is all evaporated, and the lead remains.

This preparation is used by painters under the name of vermilion; and the colour is improved by lessening the proportion of sulphur; and if a little arsenic be added in the sublimation, though the preparation is injured as a medicine, it is improved as a pigment.

An oval earthen jar is the best subliming vessel. The great art of making this cinnabar is first to manage the fire so as continually to keep the matter subliming, yet not so as to force its way through the mouth of the vessel, which is covered with an iron plate. Secondly, to put in but little at a time.

Cinnabaris graecorum. See Sanguis draco-nis.

Cinnabaris antimonii. See Antimonium.