The characters, duan ping nian zhi, refers to one of the reign periods of the Song Emperor Lizong (1234-1236).
This pendant plaque appears to be related to other large archaistic jade plaques made during the Qianlong period, such as the white jade example shaped like an axe, with chilong along the sides and a dragon at the top (13.2 cm. high), dated to the Qianlong period, illustrated in Complete Treasures of the Palace Museum - 42 - Jadeware (III), Hong Kong, 1995, p. 23, no. 18. (Fig. 1)