A mid 19th century gem-set serpent necklace. Photo:Bonhams.

The head set throughout with circular and oval cabochon turquoise, highlighted with circular cabochon garnet eyes and a cushion-shaped diamond, suspending a similarly-set heart-shaped pendant, with glazed compartment to reverse, the articulated body formed of graduated scale-like links, accompanied by a similar articulated chain, diamonds approx. 0.30ct total, convertible into a longchain, lengths: necklace 45.5cm, chain 37.4cm (2) (partially illustrated). Estimate £1,800 - 2,200 (€2,200 - 2,700)

Bonhams. JEWELLERY. 12 Feb 2014, London, Knightsbridge - www.bonhams.com