Slate Grey — Slate Grey shares the muted blue-gray of natural slate stone, giving it its name. It belongs to the Gray family: a dark, nearly neutral tone with hex code #59656D and RGB values of 89, 101, 109. Its dominant channel values give it a cool undertone that reads as nearly neutral rather than flat. Slate Grey pairs well with metallics like gold or brass for added richness and works nicely in graphic design projects. Nearest neighbors: slate.