A Colored Diamond Ring, by Van Cleef & Arpels. Photo: Christie's Images Ltd

Set with a cut-cornered modified square-cut fancy intense yellow diamond, weighing approximately 28.20 carats, flanked on either side by a triangular-cut diamond, mounted in platinum and 18k gold, in a Van Cleef & Arpels navy leather case. Signed V.C.A. for Van Cleef & Arpels, N.Y., no. 65759. Estimate $700,000 - $900,000

With report 11011963 dated 16 August 2012 from the Gemological Institute of America stating that the diamond is fancy intense yellow, natural color, VVS1 clarity; accompanied by a working diagram indicating that the clarity may be potentially internally flawless 

Christie's. Magnificent Jewels. 16 October 2012. New York, Rockefeller Plaza