sooty vs coal-black

sooty and coal-black both are adjectives.

Word	Noun	Adjective	Verb	Adverb
sooty	No	Yes	No	No
coal-black	No	Yes	No	No

As adjectives, sooty and coal-black are synonyms defined as:

sooty and coal-black: of the blackest black; similar to the color of jet or coal

Other synonyms of sooty include jet-black, jet, pitchy.

sooty (adjective)	coal-black (adjective)
of the blackest black; similar to the color of jet or coal	of the blackest black; similar to the color of jet or coal
covered with or as if with soot