A circular-cut diamond ring. Photo Christie's Image Ltd 2014

Set with a circular-cut diamond, weighing approximately 19.46 carats, flanked on either side by a tapered baguette-cut diamond, mounted in platinum. Estimate $250,000 – $450,000

With report 5161026868 dated 31 March 2014 from the Gemological Institute of America stating that the diamond is K color, VS2 clarity

Christie's. IMPORTANT JEWELS, 10 June 2014, New York, Rockefeller Plaza - http://www.christies.com/