A magnificent Type IIa diamond ring, 50.48 carats, D colour, internally flawless. Estimate Upon Request. Photo Christie's Image Ltd

Set with a pear brilliant-cut diamond, weighing approximately 50.48 carats, to the plain hoop, ring size 6½, mounted in platinum

Accompanied by report no. 5171280733 dated 28 August 2015 from the GIA Gemological Institute of America stating that the diamond is D colour, Internally Flawless clarity, with Excellent polish and Excellent symmetry, and a Diamond Type Classification letter stating that the diamond has been determined to be Type IIa. 

Christie's. GENEVA MAGNIFICENT JEWELS, 10 November 2015, Geneva