Starting in the early Northern Song dynasty (960–1127), the Xinping kilns in Jiangxi province (later renamed as the Jingdezhen kilns) developed a very fine, white-bodied porcelain. A luminous glaze with an icy blue tinge called qingbai (blue-white) was applied to porcelain to accentuate its delicacy. In his treatise Tao ji (Records on Ceramics), the Southern Song ceramic historian Jiang Qi describes it as being so pure that it rivaled jade. At its center, this qingbai bowl has a molded design of fish swimming in a lotus pond. Fish symbolize wealth in China because the character for “fish” (yu) is a homophone of the character for “abundance” (yu).