black diamond vs carbonado

black diamond and carbonado both are nouns.

Word	Noun	Adjective	Verb	Adverb
black diamond	Yes	No	No	No
carbonado	Yes	No	No	No

As nouns, black diamond and carbonado are synonyms defined as:

black diamond and carbonado: an inferior dark diamond used in industry for drilling and polishing

black diamond (noun)	carbonado (noun)
an inferior dark diamond used in industry for drilling and polishing	a piece of meat (or fish) that has been scored and broiled
	an inferior dark diamond used in industry for drilling and polishing