The form of the present cup is likely based on metalwork of the Tang through Song periods, although vessels carved from banded agate are known as early as the Tang dynasty. See an agate bowl excavated in 1995 in Xian, Shaanxi province, illustrated in Zhongguo Yuqi Quanji, vol. 5, pl. 29, where it is suggested that it was used for medicine. However, the dragon-form handle seems to appear in the Yuan or Ming dynasty, most notably on jade libation cups. Compare, for example, the cup dated to the Yuan/Ming dynasty, in the Musée Guimet, included in the exhibition, Chinese Jade throughout the Ages, and illustrated in T.O.C.S., 1973-75, no. 326, where J. Ayers and J. Rawson note that cups of such form first appeared in yingqing porcelain of the late Song dynasty and remained popular throughout the Ming.