A 'Robin's-Egg' Yixing teapot and a cover, Qing dynasty, 18th-19th century. Photo: Sotheby's

the squat square body supported on a low footrim, the C-shaped handle with a small curved thumbpiece, a high curving spout of square section, the underside with an impressed maker's seal mark possibly reading 'X peng nian zhi', covered overall in an unctuous milky-turquoise glaze with violet mottling, the associated silver cover with an agate knop, Japanese wood box and cover (4). Height 5 3/8  in., 13.6 cm. Estimation 8,000 - 12,000 USD

Provenance: An old Japanese collection before the 1950s and thence by descent. 

Sotheby's. Fine Chinese Ceramics & Works of Art. New York | 17 sept. 2013 - http://www.sothebys.com