Bronze vessels of the Eastern Zhou period (770-221 BC) differ from those of earlier times. Cast bronze vessels of the Shang dynasty (about 1500-1050 BC) and the Western Zhou dynasty (1050-771 BC) were made for ritual purposes. At the time, society was organized around family loyalties, and sacrifices to the clan ancestors were offered in various types of food and wine vessels. The bronzes were cast in moulds and were later made in sets in the Zhou dynasty.
By the Eastern Zhou dynasty, power derived from military might, and family loyalty was less important. Warlords commanded the loyalty of huge armies, whose success in war was believed to be proof of their righteousness. Display, increasingly secular, was proof of the lords' achievements. In these circumstances, weapons, chariots and furnishings became ever more important.
Bronzes had to compete with this colourful court life. Gold and silver inlay, often with the addition of semi-precious stones or glass, was developed so that the colour of the bronze vessels might match the brilliance of contemporary lacquered furnishings and textiles. This dui, a food vessel first used in the Eastern Zhou, is inlaid with silver. The triangular motif probably derived from a textile pattern. The circles may have been inset with glass.