CALAMY, Lapis Calaminaris, or Cadmia Fulgida, a sort of stone or mineral containing zinc, iron, and sometimes other substances. It is considerably heavy; moderately hard and brittle, or of a confection between stone and earth: the colour sometimes whitish or gray; sometimes yellowish, or of a deep yellow; sometimes red; sometimes brown or blackish. It is plentiful in several places of Europe, as Hungary, Transylvania, Poland, Spain, Sweden, Bohemia, Saxony, Goflar, France, and England, particularly in Derbyshire, Gloucestershire, Nottinghamshire, and Somersetshire, as also in Wales. The calamine of England, however, is by the best judges allowed to be superior in quality to that of most other countries. It seldom lies very deep, being chiefly found in clayey grounds near the surface. In some places it is mixed with lead ores. It is a true ore of zinc, and is used as an ingredient in making of brats.—Newman relates various experiments with this mineral, the only result of which was to show that it contained iron as well as zinc. The most remarkable are the following: A saturated solution of calamine in the marine acid, concentrated by evaporating part of the liquor, exhibits in the cold an appearance of fine crystals, which on the application of warmth dissolve and disappear. A little of this concentrated solution tinges a large quantity of water of a bright yellow colour; and at the same time deposits by degrees a fine, spongy, brownish precipitate. Blue dissolved in this solution, and afterwards infusillated, forms an extremely slippery tenacious mass, which does not become dry, and, were it not too expensive, might be of use for entangling flies, caterpillars, &c. Sulphur boiled in this solution, seems to acquire some degree of transparency. transparency.—This mineral is an article in the materia medica; but, before it comes to the shops is usually roasted or calcined, in order to separate some arsenical or fulphurous matter which in its crude state it is supposed to contain, and to render it more easily reducible into a fine powder. In this state it is employed in collyria against delusions of thin acrid humours upon the eyes, for drying up moist running ulcers, and healing excoriations. It is the basis of an official epulotic CERATE.

There is another substance from which this semi-metal is also obtained. This is called cadmia fornacum or cadmia of the furnaces, to distinguish it from the other. This is a matter sublimed when ores containing zinc, like those of Rammelsberg, are melted. This cadmia consists of the flowers of the semi-metal sublimed during the fusion, and adhering to the inner surfaces of the walls of furnaces, where they suffer a semi-fusion, and therefore acquire some solidity. So great a quantity of these is collected, that they form very thick incrustations, which must be frequently taken off.