POR'CELAIN, noun [Latin portulaca.]

1. The finest species of earthen ware, originally manufactured in China and Japan, but now made in several European countries. All earthen wares which are white and semi-transparent, are called porcelains, but they differ much in their fineness and beauty. The porcelain of China is said to be made of two species of earth, the petuntse, which is fusible, and the kaolin, which is not fusible, or not with the degree of heat which fuses the petuntse, and that in porcelain the substances are only semi-vitrified, or one substance only is vitrified, the other not. Hence it is concluded that porcelain is an intermediate substance between earth and glass. Hence the second degree of fusibility, of which emollescence is the first, is called by Kirwan the porcelain state.

2. The plant called purslain, which see.