A scientific study of Choson white ware: early porcelain from a royal kiln at Kwangju Usanni

Scientific study of kiln site no. 9 at Usanni, one of the earliest royal Kwangju kiln complexes in operation (from the early 15th to the early 16th century), shows that the technological expertise used to produce white ware was inherited from the celadon technology of the Koryo dynasty. The body material, of low Al₂O₃ and high SiO₂ content, is based on porcelain stone. Such a material, with almost no titanium and a low level of iron, was a rediscovery of the white ware material used earlier at the Sori kiln from the 9th century through to the 11th century. Ash continued to be one of the major ingredients of the glaze, and wares were fired in much the same way as the Koryo celadon, in kilns constructed of mud and rocks and in two steps. The Confucian philosophy and aesthetic of frugality and simplicity adopted from the Ming dynasty onwards by the new government acted as the catalyst for the successful ascent of the new technology.