A natural sponge, as opposed to a synthetic household type sponge, that is preferred for special painting techniques known as Sponging. Sponging On is a quick and simple technique that begins with the application of a solid base paint color. After the base coat dries, a wash or glaze is applied on top with a dampened sponge to create a mottled look. More than one glaze or wash color can be applied but each layer must be allowed to dry thoroughly before the next application. Lighter colors are typically applied over darker ones to create depth, but the opposite can be done for more definition and texture. Sponging Off is accomplished by applying a uniform glaze coat over the solid base with a brush or roller. Before the glaze coat begins to dry, use the sponge to remove some of the glaze to expose the undercoat.