sequin vs diamante

sequin and diamante both are nouns.

Word	Noun	Adjective	Verb	Adverb
sequin	Yes	No	No	No
diamante	Yes	No	No	No

As nouns, sequin and diamante are synonyms defined as:

sequin and diamante: adornment consisting of a small piece of shiny material used to decorate clothing

Other synonyms of sequin include spangle.

sequin (noun)	diamante (noun)
adornment consisting of a small piece of shiny material used to decorate clothing	adornment consisting of a small piece of shiny material used to decorate clothing
	fabric covered with glittering ornaments such as sequins or rhinestones