chromolithography

Chromolithography is a method for reproducing color images using lithographic techniques. In chromolithography, a separate lithographic stone or plate is prepared for each color in the image; the impressions are printed in sequence and carefully registered to produce a full-color image. The process emerged in the early 19th century, becoming widely used in both Europe and the United States through the mid-to-late 1800s. It allowed bright, durable color prints at relatively lower cost than hand-coloring, fueling the growth of illustrated books, posters, trade cards, and mass-market art. Some images used up to a dozen stones to achieve shading and depth.

The technique builds on lithography: the image is drawn with a greasy substance on a polished stone, then wetted and inked so that only the drawn areas hold the ink. For chromolithography, multiple stones or plates are prepared for each color; printing an image requires aligning the paper with each stone in turn (registration). The inks were often oil-based, producing luminous, opaque color, sometimes with hand-coloring added after printing.

In the United States, chromolithography gained popularity in the late 19th century, with firms such as Louis Prang promoting color printing for greeting cards and educational material. The method declined with the rise of offset lithography and other photomechanical processes in the early 20th century, but chromolithographs remain valued for their historical and aesthetic qualities.