Catalogue entry no. 216 by Max Loehr:
216 Biconvex Knife
Gray-green stone with light and dark brown cloud-like markings, comparable to the material seen in Nos. 195, 212, 214, and 215. Both the back, which is nearly straight, and the straight cutting edge are sharpened. The right end of the back is recessed, somewhat reminiscent of the cutout in Nos. 211 and 212, but the contour trails off in a haphazard curve. There are two conical perforations along the back; a third perforation, beneath the step where the blade narrows, is drilled from the opposite face. Early Western Chou(?).