charcoal vs charcoal grey

charcoal and charcoal grey both are nouns.

Word	Noun	Adjective	Verb	Adverb
charcoal	Yes	Yes	Yes	No
charcoal grey	Yes	No	No	No

As nouns, charcoal and charcoal grey are synonyms defined as:

Other synonyms of charcoal include charcoal gray, oxford gray, oxford grey.

charcoal (noun)	charcoal grey (noun)
a stick of black carbon material used for drawing	a very dark grey color
a drawing made with a stick of black carbon material
a very dark grey color
a carbonaceous material obtained by heating wood or other organic matter in the absence of air

charcoal (adjective)	charcoal grey (adjective)
of a very dark grey

charcoal (verb)	charcoal grey (verb)
draw, trace, or represent with charcoal