Jade three-tooth wall

[Jade three-tooth wall]

Jade three-tooth wall, Shang, outer diameter 15.2 cm, inner diameter 6.2 cm, thickness 0.6 cm
White jade, with a large amount of sugar color on the periphery of the jade, part of the chicken bone has been albino on the outer edge, and there are yellowish-brown spots. The body is flat and round, with a straight cut mark and a hole in the middle. The wall has three teeth, which are in a rotating shape, with four teeth on each tooth
The appearance of Yabi from the Neolithic Age lasted for two weeks. For a long time, there have been different opinions about the use of tooth wall. Many scholars believe that it is the Xuan Ji in the “Xuan Ji Yu Heng, Qi Qi Qi Qi Qi Zheng” mentioned in the “Book of Shang Shu Shun Dian”, and it is an ancient astronomical instrument for observing celestial phenomena with jade, so it has long been named Yu Xuan Ji; Others think it is an ancient weapon or mechanical part; Other scholars tend to believe that it has a certain ceremonial nature, not a practical tool, but a divine tool