CALX ANTIMONII, is the earthy part of the regulus of antimony when deprived of its phlogiston. See PHARMACY, no 791. By the mere action of fire, however, the whole of its phlogiston cannot be dissipated; though it may be done by the addition of nitre, and the calx become perfectly white; but in this case it cannot be melted into glass, except in the focus of a burning mirror. The calx of antimony, perfectly deprived of its phlogiston, has been used in medicine chiefly under the name of diaphoretic antimony; but little regard is now paid to it.