[ 'kju:p(ə)l ]
■ noun a shallow, porous container in which gold or silver can be refined or assayed by melting with a blast of hot air which oxidizes lead or other base metals.
■ verb ( ~s , ~ling , ~led ; US ~s , ~ing , ~ed ) assay or refine (a metal) in a ~.
Derivatives
~lation noun
Origin
C17: from Fr. coupelle , dimin. of coupe 'goblet'.