Painted pottery The production process of the painted pottery with a piece of mouth is similar to other painted pottery. First, the blank is fired into the shape of a vessel, then the surface of the vessel is coated with black glaze, and then red and white patterns are drawn on the black glaze. Finally, the glaze is burned to form a bright color pattern. The first-class cultural relics displayed in Guyuan Museum also belong to this kind of material.