Rare bronze worth £1.5m spent years in cupboard

A renaissance treasure that lay unloved in a cupboard under the stairs of a stately home for decades has been found, and valued at £1.5m.

The 42cm gilded bronze roundel had never been documented and was unknown to academics until it was found in the estate of an English family.

The bronze was probably acquired on a Grand Tour of Europe in the 1740s by George Treby III, from a rich family of 18th-century MPs. It was made near Mantua, northern Italy, late in the 15th century, almost certainly by the same person who created a relief in the Kunthistorisches Museum in Vienna, possibly a goldsmith called Gian Marco Cavalli.

Donald Johnston, a Christie's expert, said: "It is fantastic quality, incredibly early and rare, and it was completely unknown. It's hugely exciting."