Production color low temperature lead glazes in the Tang dynasty. Use white clay as a child, containing copper, iron, cobalt, manganese and other elements of the mineral as a glaze colorant, and add a big lead in the glaze of slag and lead ash as flux, after about 800 degrees centigrade temperatures firing from. Glazed dark green, light green, emerald green, blue, yellow, white, ocher, Brown and other colors, but dominated by yellow, green and white color. Tri-colored glaze to lead oxide, as a flux in order to reduce the melting temperature of glaze. In the firing process, various colored metal molten oxide in lead glaze, natural diffusion and circulation, and variety of colors each other infiltrates, forming mottled bright glaze. Lead also increases the glazed surface brightness, and color even more beautiful.