MIDDLE WESTERN ZHOU DYNASTY, 10TH-9TH CENTURY BC

Pan were shallow basins used as ritual vessels to hold water. They were used in conjunction with a he or a yi to form a set of vessels for the washing of hands. Such vessels would have been included in the ritual vessel sets "required by an individual or family of a given period to perform the customary ritual food and wine offerings to the ancestors." See J. Rawson, Western Zhou Ritual Bronzes from the Arthur M. Sackler Collections, vol. IIA, The Arthur M. Sackler Foundation, 1990, p. 98. Such a set, of Middle Western Zhou date, from Shaanxi Fufeng Qijiacun M19, is illustrated in a line drawing, ibid., p. 99, fig. 142d.
A very similar pan of comparable size (42.3 cm.) is illustrated by J. A. Pope et al. in The Freer Chinese Bronzes, vol. I, Washington, 1967, pl. 82.