The form of the present vase is closely related to a Longquan celadonglazed fanghu in the National Palace Museum, Taipei, illustrated in Porcelain of the National Palace Museum - Lung-chuan Ware of the Sung Dynasty, Hong Kong, 1962, p. 28, pl. 1 (fig. 1), which is incised on the base with an imperial poem composed by Emperor Qianlong and titled yong guangyao shuanger ping, Praising a Guanyao doublehandled vase, suggesting that the Emperor may have erroneously identified it as Guan. The present vase is extremely rare, as no other Ru-type Qianlongmarked example appears to have been published. Similar Yongzhengmarked examples are known, including one sold at Christies Hong Kong, 26 April 2004, lot 946, and another sold at Sothebys Hong Kong, 23 October 2005, lot 319. Compare also to a Yongzheng-marked Ge-type glazed variant in the National Palace Museum, Taipei, illustrated in Catalogue of the Special Exhibition of Kang-his, Yung-cheng and Chien-lung Porcelain Ware from the Ching Dynasty in the National Palace Museum, Taipei, 1986, no. 63.