Bi disc

Originating in the Hongshan culture of the Neolithic period, around 4000 to 3000 BCE, the bi disk is emblematic of heaven. The bi disks from the later Han dynasty tend to be more elaborate. The outer band of this bi is decorated with openwork designs of four dragons. Dragons were believed to have the power to control heaven, suggested here by the dragons fully surrounding the disk. The raised bosses toward the center of this bi (known as guwen or “grain pattern”) are simpler in comparison to earlier Western Han examples, which were accompanied by incised spirals signifying sprouting grain—perhaps a symbol of fertility. By the late Han dynasty, the curving tails of the grains became less obvious or disappeared completely, as seen here.