Dated examples of Chongzhen period porcelain are exceedingly rare. A blue and white incense burner decorated with dragons pursuing a pearl, cyclically dated to the ding chou year of Chongzhen (1637) is illustrated by S. Riddell in Dated Chinese Antiquities, 600-1650, London, 1979, p. 111, no. 98. See, also, a pair of bowls decorated with Daoist trigrams around a central yinyang symbol, dated to the third quarter of the sixteenth century, illustrated by R. Krahl and J. Ayers in Chinese Ceramics in the Topkapi Saray Museum, Istanbul, vol. II, London, 1986, p. 639, no. 951.