In printmaking, an engraving process that is tonal rather than linear, or prints produced by this process. Developed in the seventeenth century, mezzotint was used widely as a reproductive printing process, especially in England, until photographic processes overtook it in the mid-nineteenth century. Mezzotints were most commonly produced from 1780s-1870s. A copper or steel plate is first worked all over with a curved, serrated tool called a rocker, raising burrs over the surface to hold the ink and print as a soft dark tone. The design is then created in lighter tones by scraping out and burnishing areas of the roughened plate so that they hold less ink, or none in highlights. Details may be sharpened by engraving or etching in a "mixed mezzotint."Some characteristics of mezzotints: The plate's surface is roughened to a texture of fine sand paper. The plate's surface is then burnished to produce lighter tones. The image exhibits an irregular sandy grain structure, and an occasional linear pattern may be detected. Examples: James MacArdell, after a painting by C. Jansens, William Harvey. M.D. (1578-1657), n.d., mezzotint, 28.5 x 23.2 cm, published by Charles J. Sawyer, London.William Say (English engraver, 1768-1834), after a painting by Sir Joshua Reynolds (English, 1723-1792), Sir William Hamilton and Society Dilettante, c. 1780s, mezzotint, 25 1/2 x 18 1/2 inches. See dilettante.Related links: "The Illustrated Book Study" is a collaborative effort undertaken by Cornell University Library's Department of Preservation and Conservation and Picture Elements, Inc, and the Library of Congress. On its Illustrated Book Study Resolution Samples pages, visitors can examine digital images of prints of several types ? collotype, copper engraving, etching, halftone, lithograph, mezzotint, photogravure, steel engraving, and wood engraving ? at each of several resolutions ? dots per inch (DPI).