Late Neolithic Period to Early Bronze Age (ca. 3000-1800 B.C.)
Max. diameter: 6.1 cm, diameter of hole: 2.3 cm,
thickness: 1.0 cm
??This dark yellow jade has striations and is lustrous. It was probably worked from the center cut-out of a pi disk. The edge is slanted, but the wall of the hole is straight. It also includes a wooden stand specifically made for it.
??This reworked jade from a pi disk center has evidence of circular drilling along the slanted edge, and the hole was drilled from one side. Excavations from Ch'i-ch'ia Culture sites in Kansu and Ning-hsia provinces have revealed many such pi disk centers, and they are similar to this one.