During the heyday of Goryeo celadon between the late twelfth and thirteenth century, various decorative styles of jade-colored celadons - such as plain, intaglio carving, relief carving, impressed engraving in relief, pictogram, openwork, and underglaze iron brown - were developed, culminating in sanggam inlaying, Goryeo’s renowned and unique pattern carving technique. Sanggam inlaying is an advanced decorative technique in which craftsmen would engrave an item of pottery with lines or designs, and then insert materials such as white clay or porcelain clay into them, in order to create an attractive colored effect. It was widely used not only on pottery but also on metal craftworks (metalwork inlaid with gold and silver) and wooden craftworks (lacquerware inlaid with mother-of-pearl). Common decorative themes included cranes flying freely through clouds, floral patterns consisting of chrysanthemums or peonies, water birds swimming in a body of water surrounded by reeds and a willow tree, and so on. The main production areas of Sanggam celadon were Buan in Jeollabuk-do and Gangjin in Jeollanam-do, and their products were distributed to Gaegyeong, and from there to all over the country by sea.