The glaze on the present vase is based on that of Song-dynasty Ge ware, one of the ‘five famous wares of the Song dynasty’. Song-dynasty wares were highly admired by the Yongzheng emperor, a keen antiquarian who collected and studied material from earlier dynasties. His extensive interest in ancient artworks is reflected in two scroll paintings entitled Guwan tu, "Pictures of Ancient Playthings," which act as inventories, depicting antiques in the Imperial collection during his reign. One such scroll is in the collection of the Victoria and Albert Museum, London, and the other in the Percival David Collection now housed in the British Museum, and both are illustrated in China: The Three Emperors, 1662-1795, Royal Academy of Arts, London, 2005, pp. 252-55, nos. 168 and 169. The array of fine examples of Song-dynasty Ge wares seen in these scrolls is a testament to the emperor’s appreciation of this particular glaze. The Yongzheng emperor is recorded to have specifically ordered that porcelain wares imitating the various stoneware glazes of the Song dynasty be produced at the imperial kilns in Jingdezhen. In fact, the famous kiln director Tang Yin became particularly well-known for the success of these imitation Song wares. Some of the finer imitation wares bear imperial reign marks, as seen on the base of the present vase.
The Ge-type glaze on the Irving vase is exceptionally successful, achieving the silky feel and subtle interaction of the pale greyish-blue tone interspersed with the darker, sprawling crackle, even on the base. The vase displays the sensitivity of the Yongzheng-period potters to the original Song-dynasty prototypes, by the use of a dark brown slip on the foot rim to conceal the underlying white porcelain body in imitation of the the dark brownish-grey body associated with Song Ge wares. The combination of the five-lobed form and delicate size of this vase appear to be very rare, but an almost identical example, also Yongzheng mark and of the period, is in the collection of the Palace Museum, Beijing, illustrated in Selection of Ge Ware: The Palace Museum Collection and Archaeological Discoveries, 2017, pp. 270-71, no. 132.