Wiktionary
n. (context arts English) A technique in which drawings are created using sharp knives and tools for etching into a thin layer of white china clay that is coated with black India ink
Wikipedia
Scraperboard or scratchboard refers to both a medium, and an illustrative technique using sharp knives and tools for etching into a thin layer of white China clay that is coated with black India ink. Scratchboard can also be made with several layers of multi-colored clay, so the pressure exerted on the instrument used determines the color that is revealed. There is also foil paper covered with black ink that, when scratched, exposes the shiny surface beneath. Scratchboard can be used to yield highly detailed, precise and evenly textured artwork.
Usage examples of "scratchboard".
That Sunday morning in September, we were at the fan-art exhibit, and I was stopped in front of a display of scratchboard illustrations by a young man named Dennis Smith, from Chula Vista, California.
Snow winnowed down like Crosshatch in scratchboard through the weathered slats of the corncrib, while seconds fled, closing the interval left before midnight.
Lyle stared at it, pleased, and the light sketched chilly blue-white highlights over his bare scalp, down his nose, along his upper lip, and across his chin like a scratchboard drawing on the brown of his skin.