TWO HARDSTONE 'BI' DISCS, China, Liangzhu Culture, 3rd millennium BC. The green disc is evenly patterned. The inner hole was drilled from both sides and has a diameter of 3.5 cm. - Green disc from an important German private collection, bought in the 1970s. The dark-brown disc was acquired at Ralph M. Chait Galleries Inc., New York, 9 Sep 1967 - Cf. Yang Boda, Chinese Archaic Jades from the Kwan Collection, no. 40 as well as Rawson, Jessica, Chinese Jade from the Neolithic to the Qing, no. 4:3, p. 133-134; A very similar disc was sold at Christie's New York, 19.03.2015, Lot 471 - Minor chip and very minor wear to the rim