How it began
In the mid-twelfth century potters of the Goryeo dynasty began using an inlay technique called sanggam to decorate celadon. Celadon production in Korea had started in the second quarter of the tenth century around the Goryeo capital, Gaeseong, and from the late eleventh to the early thirteenth centuries kilns were established at Gangjin, in today's South Jeolla province in South Korea, where clay, firewood and a natural port were at hand. The royal court invested heavily in celadon and its ornamentation.
Before it existed
Goryeo potters first learned celadon technology from Song-dynasty China, especially its southern coast, and early pieces emulated Chinese forms. To get a consistent blue-green color they developed a two-step firing and used traditional mud kilns that blocked the flow of oxygen. Before inlay, decoration relied on molds, on incised lines in which the glaze pooled, and on painted underglaze iron and copper pigments.
How it works
The potter stamps or carves the design into the dry clay body and fills the hollowed space with white or black slip, a mixture of clay, water and usually a mineral pigment. The piece is given a first bisque firing, then the translucent celadon glaze is applied and the vessel is fired again in a low-oxygen atmosphere. The pale and dark inlays show through the green glaze as crisp motifs such as cranes and clouds.
How it spread
Gangjin shipped large quantities of celadon by sea to the capital for the court and nobility, and Goryeo celadon traveled on to China and Japan. A ship that left Ningbo for Japan and sank off Korea's southwest coast in 1323, excavated in 1976, carried seven Goryeo celadon vessels chosen for the Japanese market. Goryeo celadon is also found at many medieval Japanese sites, where monks, townspeople, military elites and nobles collected it.
What lasted
Inlaid celadon is regarded as the culmination of Goryeo celadon and was a rarity in China, so it came to stand for a distinctly Korean ceramic style. Song-dynasty writers praised Goryeo celadon; the envoy Xu Jing, who visited in 1123, noted its craftsmanship, and another author listed the jade-colored celadon of Goryeo among the best things under heaven. Goryeo celadons are the earliest Korean ceramics studied for their art historical value.
