bone-ash cup vs cupel

bone-ash cup and cupel both are nouns.

Word	Noun	Adjective	Verb	Adverb
bone-ash cup	Yes	No	No	No
cupel	Yes	No	No	No

As nouns, bone-ash cup and cupel are synonyms defined as:

bone-ash cup and cupel: a small porous bowl made of bone ash used in assaying to separate precious metals from e.g. lead

Other synonyms of bone-ash cup include refractory pot.

bone-ash cup (noun)	cupel (noun)
a small porous bowl made of bone ash used in assaying to separate precious metals from e.g. lead	a small porous bowl made of bone ash used in assaying to separate precious metals from e.g. lead