Mezzotint is among the most physically demanding mediums in art, one tried and quickly abandoned as "too difficult", for example, by the great printmaker M.C. Escher. A copper plate is "rocked" with a curved, notched blade until the surface is entirely pitted. At this stage, an inked plate would print a rich, uniform black. The artist then uses a scraper or burnisher to flatten the raised parts, a little for dark grays, a lot for light grays, completely for white (after inking and wiping, the plate holds no ink where it is smooth). Colors are achieved by similarly working one or more supplementary plates.