An aquatint is an etching in mass instead of in line; like conventional etchings, aquatint relies upon the use of a copper or zinc printing plate, nitric or hydrochloric acid, and an intaglio printing press. Its tonal quality is made possible by the application to the plate of a special ground, which consists of powdered resin. Warming the plate fuses the resin particles to it causing them to form an acid resisting ground of granual texture. When the plate is immersed in acid the acid bites through the points unprotected by the fused resin particles producing solid areas of granular tone. The depth of this tone is determined by how long the plate is immersed, and by using a liquid acid-resisting varnish the printmaker can make specific areas of the design lighter or darker. The completed plate is then inked, wiped, and printed in the same manner as an etching. The aquatints here are hand-colored with watercolor after the ink has dried.