Originated in the Song Dynasty, hare's fur glaze is a lively description of porcelain with rust crystal stripes on black glaze. Iron is used as coloring agent in the glaze. As it contains a small amount of calcium phosphate, when the firing humidity rises to about 1000℃, part of the glaze begins to melt, and the glaze layer close to the matrix becomes strongly connected with it. The glaze without contact with the matrix on the surface flows downward because of the melting. Devitrification and crystallization therefore happen simultaneously, causing the glaze surface to produce stripes looking like hare's fur. After the founding of the People's Republic of China, Boshan Ceramic Factory produced color glaze which was sold all over the world, including hare's fur glaze.