A fine and large rhinoceros horn carved cup, 19th century. photo Bonhams

Deeply hollowed and well carved along all the length of the curving tusk, below the plain cup carved as a flower head, with small figures singly and grouped scattered irregularly through a ground of scrolling lingzhi, pine, magnolia and other foliage, the surface dark patinated and with a lustrous polish. 56cm (22in) long. Estimate: £30,000 - 50,000, HKD 380,000 - 630,000, $ 49,000 - 82,000

Provenance: an English private collection

Another example of this unusually large long horn is in the collection of the Henry Francis du Pont Winterthur Museum, Delaware, illustrated by Carl L.Crossman, The Decorative Arts of the China Trade, Suffolk, 1997, pl.178. The author notes that this one is probably to be dated before 1840.

Bonhams. Fine Chinese Art, 12 May 2011, New Bond Street www.bonhams.com