Aquatint is a method of etching upon copper plates. Aquatint creates a pleasing, shaded, granular texture. In aquatint, the artist first scatters powdered rosin uniformly over a metal plate. When warmed, the rosin grains stick to the plate without combining. This process leaves tiny portions of the metal open to the action of an acid. The acid bites (eats into) the metal around the edges of the grains. The length of biting controls the range of light and dark tones. Artists seldom use straight aquatint. They usually combine it with etching or engraving and various acidproof coatings.