Technical similarities and improvisatory designs point to the celadon tradition of the late Koryo as the source of early punch’ong. For example, hand-carved inlay had by that time been simplified to stamped designs, a type of decoration that was fully exploited in punch’ong. The most innovative punch’ong wares are decorated with sgraffito designs of striking vibrancy or brushed with slip, creating startlingly abstract and dynamic patterns.