Jar 7th-early 8th century China In the eighth and ninth centuries, technically advanced Xing wares were the rarest and most valued ceramics in Asia. Some are known to have been used at the Chinese court. Others were either diplomatic gifts or trade goods sent to centers such as the Abbasid court in Iraq, where they inspired poetry comparing them to the luster of a pearl or of the moon.. Jar. China. 7th-early 8th century. Porcelain with white glaze (Xing ware). Tang dynasty (618-907). Ceramics