A plate mark is the rectangular indentation pressed into the paper of an intaglio print by the edges of the metal plate as it passes through the printing press under heavy pressure. It is found on engravings, etchings, mezzotints, aquatints and drypoints, and appears as a slight ridge or bevelled line just outside the printed image.
The plate mark is one of the first features examined when assessing an old print. Its presence usually indicates that the image was printed from an engraved or etched plate, whereas lithographs, woodcuts and photomechanical reproductions printed by other methods do not normally show one. It is not, however, an infallible test, as some later reproductions have had false plate marks embossed into the paper to give an appearance of authenticity. A print trimmed inside the plate mark, or within the image, is generally less desirable than one with full margins, and a crisp, unflattened plate mark suggests the paper has not been heavily pressed or relined. Collectors also consider paper type, watermarks, the quality of the impression and condition, including foxing and staining. Careful framing with a window mount that reveals the plate mark is often preferred.
