A similar mirror of comparable small size (6 cm.) is illustrated in Ancient Bronze Mirrors from the Shanghai Museum, Shanghai, 2005, pp. 236-7, no. 80; and two others of comparable size are illustrated in Luoyang chutu tongjing (Bronze Mirrors Excavated in Luoyang), Beijing, 1988, nos. 115 and 116. See, also, the similar mirror illustrated by T. Nakano et al., Bronze Mirrors from Ancient China: Donald H. Graham Jr. Collection, 1994, pp. 230-1, no. 85, where the authors note that the practice of decorating the backs of bronze mirrors with silver or gilt-silver sheet with repoussé decoration is first seen in the Sui dynasty, but was most popular in the mid-eighth century on lobed mirrors. Miniature mirrors such as this were probably portable and carried by noblewomen.