slaty vs slaty-grey

slaty and slaty-grey both are adjectives.

Word	Noun	Adjective	Verb	Adverb
slaty	No	Yes	No	No
slaty-grey	No	Yes	No	No

As adjectives, slaty and slaty-grey are synonyms defined as:

Other synonyms of slaty include slate-gray, slate-grey, slatey, slaty-gray, stone-gray, stone-grey.

slaty (adjective)	slaty-grey (adjective)
of the color of slate or granite	of the color of slate or granite