1. a small porous bowl made of bone ash used in assaying to separate precious metals from e.g. lead; [syn: bone-ash cup, cupel, refractory pot]
WordNet (r) 3.0 (2006):
bone-ash cup
n 1: a small porous bowl made of bone ash used in assaying to
separate precious metals from e.g. lead [syn: bone-ash
cup, cupel, refractory pot]