Catalogue entry no. 587 by Max Loehr:
587 Large, Heavy Disk with Patterns of Spirals in Concentric Circles
Variegated green, gray, and yellowish brown stone disk with a biconical perforation. Both sides are covered with flat, rounded elevations in eleven concentric rows. A crudely incised curve on top of each of the elevations makes them resemble spirals. This technique is distinct from those of the previous described disks with spiral or curved decoration. The surface is even but without a high polish. Han or later.