Catalogue entry no. 495 by Max Loehr:
495 Pair of Oblong Tablets
Dark gray-green translucent jade with brown markings, fashioned into sharp-cornered, rectangular, flat tablets. Their sides are scored by five notches placed at even intervals. Between the similarly notched and longitudinally perforated ends runs a narrow median slit. The upper and lower surfaces display a pattern of incised spirals; cross-hatching appears along the notches, and slanting striae at either side of the slits. Late Eastern Chou(?).