Notched disk

Three sweeping arcs on the disk feature a pattern of serrated fins. Unlike standard Neolithic disks with perfectly circular perimeters and a central hole, this later form exudes both energy and movement. As a geometric figure, it also projects a sense of precision even though the different units are not identical in length, height, or spacing. This irregularity contributes to the disk’s visual appeal.

One face of the disk features inscribed, perpendicular lines. In his Gu yu tukao, the Qing-dynasty scholar Wu Dacheng (1835–1902) postulated that these intriguing markings could be associated with an astronomical instrument called xuanji, described in early ritual texts as a kind of armillary sphere or model of heavenly bodies. Extremely interesting pseudomorphs—mineralized replacements preserving contact with an ancient pattern, possibly from a painted container—are also visible on this side.

Notched disks like this one are rare, and only a few have come from known archaeological contexts. The documented burials span the late Neolithic through the Western Zhou period (circa 1050–771 BCE), suggesting that treasured examples may have been preserved for long periods of time prior to burial. Unfortunately, none of the archaeological contexts is described in adequate detail to reveal the disks’ purpose in burial. Made from a similar material that has likewise weathered to a creamy gray-green, the excavated notched disk that most closely resembles this one was found at a late Neolithic Longshan culture site at Teng xian, Shandong Province. That piece is one-quarter the size of the Freer example.

Based upon archaeological evidence, specialists such as Xia Nai of the Chinese Institute of Archaeology and Christopher Cullen, director emeritus of the Needham Research Institute at Robinson College, Cambridge, have argued that notched disks like this one should simply be seen as a later, special type of bi disk. Their argument overturns Wu Dacheng’s astronomical theory, which was based upon textual study.

This disk was acquired by the renowned collector David David-Weil (1871–1952) in 1934 and was retained by his family until 2016. It is significantly larger than the five others already in the Sackler collection (S1987.454-456, S1987.932, and S2012.9.217).