J`ASPER, n. [L. iaspis.] A mineral of the siliceous kind, and of several varieties. It is less hard than flint or even than common quartz, but gives fire with steel. It is entirely opake, or sometimes feebly translucent at the edges, and it presents almost every variety of color. Its varieties are common jasper, striped jasper, Egyptian jasper, &c. It admits of an elegant polish, and is used for vases, seals, snuff-boxes, &c.
Jasper is a subspecies of rhomboidal quartz, of five kinds, Egyptian, striped, porcelain, common, and agate jasper.