Richard A. Pegg. Early Pottery Traditions of the Pearl River Valley and Red River Valley Delta
Stoneware emerged during the middle of the Shang period (c. 1550–1050 BCE), along the eastern coast to the south of the Yangzi river, in the region of the Yue kingdom. It developed with the discovery of iron-rich clay along with the required technological advances of high-temperature firing. During the ensuing Warring States period (480–222 BCE), decoration with applied, impressed, or incised geometric patterns continued to advance. With the transfer of the technology and more widespread discovery of the proper materials, stoneware began to be produced further north and south of this area.