Catalogue entry no. 98 by Max Loehr:
98 Collared Disk
Small, narrow disk with a collar around the inner edge. Greenish black stone with light gray streaks on one side. The collar projects on one side, while on the other side it is ground down to a low ledge. Slight depressions running tangentially on both sides of the disk give evidence of the laborious grinding process. Shang or Western Chou.