Definition of "slate-blue" [slate-blue]

• Dull-blue with a grayish tinge; schistaceous.

The Century Dictionary (Public Domain)

• "With pedestals blending into the slate-blue shades of the walls, the artworks appear to float in a timeless space, enhancing the sense that every piece is but a fragment from a rich past."
• "Half his head blown across the tweed seat covers, the windshield, the back window, the side window, even the slate-blue console."
• "An Asian telephone bidder paid Sotheby's $11.5 million for Mr. Richter's creamy 1990 "Abstract Picture" on Tuesday; the following night, a Russian-speaking telephone bidder paid Christie's $5.1 million for a smaller, slate-blue "Abstract Picture" the artist created that same year."