A rare 'Qingbai' 'Duck' box and cover, Southern Song Dynasty. Estimate 10,000 — 15,000 USD. Photo Sotheby's

in the form of two conjoined circular boxes, the covers of conforming shape carved with two recumbent ducks, its feathers incised with details, covered overall in a translucent glaze tinged with blue, the interior of the covers, interior rims and base left unglazed revealing the white body (2). Length 3 5/8  in., 9.2 cm

Sotheby's. Important Chinese Works of Art, New York, 17 mars 2015, 02:00 PM