Decalcomania is a technique used in art that involves transferring patterns or designs from one surface to another. The method involves pressing a surface with a design or pattern onto another surface, such as paper or canvas, and then peeling it off to create a unique and unpredictable pattern.

The technique was invented in the 18th century, and was used to create decorative patterns on ceramics and other objects. It was later adopted by surrealist artists in the early 20th century, who used it to create abstract and dreamlike images.

The most famous example of decalcomania in art is the work of the surrealist artist Max Ernst, who used the technique to create his “frottage” and “grattage” works. Ernst would press a piece of paper onto a rough surface, such as a floorboard or a piece of wood, and then rub a pencil or other drawing tool over the paper to create a pattern. He would then use this pattern as a starting point for his drawings and paintings.

Other artists, such as Salvador Dali and Joan Miro, also used decalcomania in their work, and the technique continues to be used by artists today to create unique and unpredictable patterns and textures.