kulla ja hõbeda eraldamine pliist kupellimistiiglis (vt kupellimistiigel, kupellimine), väärismetalle sulameist või maakidest eraldama neid kupellis sulatades oksüdeeriva leegi abil, the operation employed in recovering gold and silver from lead involving the melting of the lead containing these metals and its oxidation by means of an air-blast (see: cupel, cupellation)