A diamond single-stone ring. Photo Bonhams.

The marquise-cut diamond, weighing 4.27 carats, between tapered baguette-cut diamond shoulders, ring size L. Estimate £60,000 - 80,000 (€73,000 - 97,000)

ccompanied by a report from AnchorCert stating that the diamond weighing 4.27 carats is E colour, Internally Flawless, Type IIa. Report number 20014488, dated 31 January 2014.

Bonhams. FINE JEWELLERY. London, New Bond Street, 30 Apr 2014 -www.bonhams.com