A sapphire and diamond cluster ring. Photo: Bonhams.

The oval-cut sapphire, weighing 6.59 carats, within a cluster of old brilliant-cut diamonds, diamonds approximately 1.00 carat total, ring size N. Estimate £10,000 - 12,000 (€12,000 - 14,000)

Accompanied by a report from Gϋbelin stating that the sapphire is of Sri Lankan origin, with no evidence of heat treatment. Report number 14010199, dated 29 January 2014.

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