mother-of-pearl vs nacre

mother-of-pearl and nacre both are nouns.

Word	Noun	Adjective	Verb	Adverb
mother-of-pearl	Yes	No	No	No
nacre	Yes	No	No	No

As nouns, mother-of-pearl and nacre are synonyms defined as:

mother-of-pearl and nacre: the iridescent internal layer of a mollusk shell

mother-of-pearl (noun)	nacre (noun)
the iridescent internal layer of a mollusk shell	the iridescent internal layer of a mollusk shell