Disk (<em>bi</em> 璧)

Perforated disk of the type pi [bi] 璧; bored mostly from one side leaving slight ridge; obverse of mottled pastel tones of gray, cream, white, and pink, reverse is creamy white and gray; both surfaces have rough areas of unpolished granular gray rock and the whole substance is a fusion of many shapes and materials; white encrustation and incipient disintegration. (Pitted areas, cracks, and fissures on rim and surfaces.)