[ noun ] a small porous bowl made of bone ash used in assaying to separate precious metals from e.g. lead <noun.artifact>
Cupel \Cu"pel\ (k[=u]"p[e^]l), n. [LL. cupella cup (cf. L. cupella, small cask, dim. of cupa) : cf. F. coupelle. See {Cup}, and cf. {Coblet}.] A shallow porous cup, used in refining precious metals, commonly made of bone ashes (phosphate of lime). [Written also {coppel}.]
{Cupel dust}, powder used in purifying metals.
Cupel \Cu*pel"\ (k[-u]*p[e^]l"), v. t. [imp. & p. p. {Cupelled} (-p?ld"); p. pr. & vb. n. {Cupelling}.] To refine by means of a cupel.