A sapphire and diamond ring, by Tiffany & Co. Photo Christie's Image Ltd 2014.

Set with a cushion-shaped sapphire in an old-mine cut diamond surround, mounted in gold, ring size 6¼. Signed Tiffany & Co. Estimate CHF40,000 – CHF50,000 ($45,683 - $57,104)

Accompanied by report no. 66105 dated 6 December 2012 from the SSEF Swiss Gemmological Institute stating that the sapphire is of Kashmir origin, with no indications of heating

Report no. 14030048 dated 13 March 2014 from the Gübelin GemLab stating that the sapphire is of Kashmir origin, with no indications of heating

Christie's. GENEVA MAGNIFICENT JEWELS, 14 May 2014, Geneva - http://www.christies.com/