Lithograph

Lithography is a printing process based on the principle that water and oil do not mix. To create an image, the artist uses a greasy crayon or ink to draw onto a limestone block or metal plate. This image is then chemically treated so that the grease adheres to the stone or plate. Any excess is removed before printing. The printer then sprays the stone or plate with water and covers it with oil-based ink. The oily ink sticks only to the greasy image areas, while the water repels it from the areas without the image. Finally, the image is transferred to paper with a printing press. Each color requires a separate stone or plate. Artists often choose this method because they can use the crayons and brushes to create delicate and painterly effects.