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.