A three-stone 4.55 carats Kashmir sapphire and diamond ring. Estimate $330,000 – $400,000. Photo Christie's Image Ltd 2015

Set with a cushion-cut sapphire, weighing approximately 4.55 carats, flanked on either side by a modified cushion-cut diamond, weighing approximately 1.55 and 1.50 carats, mounted in platinum.

With report 14037214 dated 5 March 2014 from the Gübelin Gem Lab stating that gemmological testing revealed characteristics consistent with those of sapphires originating from Kashmir. No indications of heating

With report 73195 dated 12 March 2014 from SSEF Swiss Gemmological Institute stating that the origin of this sapphire is Kashmir. No indications of heating

With report CS 83342 dated 14 March 2014 from the American Gemological Laboratories stating that it is the opinion of the Laboratory that the origin of this sapphire would be classified as Kashmir. No gemological evidence of heat

With report 2146708435 dated 21 March 2013 from the Gemological Institute of America stating that the diamond, weighing approximately 1.55 carats, is D color VVS1 clarity, with excellent polish and excellent symmetry

With report 6157250969 dated 16 February 2013 from the Gemological Institute of America stating that the diamond, weighing approximately 1.50 carats, is D color, VVS2 clarity

Christie's. MAGNIFICENT JEWELS, 14 April 2015, New York, Rockefeller Plaza