A carnelian intaglio ring, by Nathaniel Marchant (1739-1816). Estimate £8,000 - 10,000 (€11,000 - 14,000). Photo: Bonhams.

The collet-set carnelian plaque carved to depict Pericles wearing a Corinthian helmet in profile to the left, mounted in a later gold collet-setting, intaglio signed Marchant, intaglio length 2.6cm, ring size M

Notes: Nathaniel Marchant (1739-1816) was probably the most famous gem engraver of the 19th century, being prolific in both Italy and England. He was gem sculptor to The Prince of Wales and engraver to The King.

Marchant's love of the classical subject matter was well developed and he produced many depictions of the Athenian statesman Pericles. A very similar depiction is known, casts of which are on display at the Ashmolean Museum, Oxford and at the Sir John Soane Museum, London. Of note is that this intaglio bears a non mirrored signature, something Marchant, like his tutor Edward Burch, was well known for. Carnelian was a popular material for much of Marchant's early pieces, which suggests this may be an early example of his work.

Bonhams. JEWELLERY, 9 Sep 2015 11:00 BST - LONDON, KNIGHTSBRIDGE