Official seal

The knob of this seal as well as its inscription indicate that it was used to stamp official documents. During the Shang dynasty (c. 1600-1050 BCE), tortoise shells were used in divination rituals, in which a hot poker was applied to the shell until it cracked. The cracks were then interpreted by a shaman to communicate with gods and foretell the future. Tortoises are also thought of as symbols of longevity and tenacity, and thus were considered auspicious beings. Tortoise knob seals were used by officials during the Han dynasty, as evidenced by several examples bearing official inscriptions that were excavated from Han tombs. This seal bears the inscription Taishou zhang (“the governor’s seal”), indicating that it was the seal of a governor, or taishou.