stone-gray has definitions from the field of color
1
[ adjective ] (color) of the color of slate or granite

Examples

"the slaty sky of dawn"

Used in print

(Clayton C. Barbeau, The Ikon....)

Brittany , that stone-gray mystery through which he traveled for thirty days , sleeping in the barns of farmers or alongside roads , had worked some subtle change in him , he knew , and it was in Brittany that he had met Pierre .

Related terms

achromatic

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