Cloisonn é, one of the famous special metal crafts in China, reached its peak in production during the Jingtai period of the Ming Dynasty, producing the most exquisite and famous crafts. Therefore, later generations referred to this metal artifact as "Cloisonn é". Cloisonn é, officially known as "Copper Cloisonn é Enamel" or "Enamel Cloisonn é", is a type of utensil made of soft flat copper wire that is cut into various patterns and welded onto a copper mold. The enamel is then filled into the patterns and fired. Due to its popularity during the Jingtai period of the Ming Dynasty and mature production techniques, the enamel glaze used was mostly blue, hence the name "Jingtai Blue".