An impressive 22.09 carats Type IIa diamond ring and A fine 15.08 carats Burma sapphire and diamond ring, by Bvlgari. Photo Christie's Image Ltd 2015

An impressive 22.09 carats Type IIa diamond ring. Estimate $1,300,000 – $1,500,000. Photo Christie's Image Ltd 2015

Set with a circular-cut diamond, weighing approximately 22.09 carats, to the circular-cut diamond hoop, mounted in platinum, ring size 6

With report 1162547321 dated 25 November 2014 from the Gemological Institute of America stating that the diamond is H color, VVS1 clarity, with excellent cut, polish and symmetry

Accompanied by a supplemental letter from the Gemological Institute of America stating that the diamond has been determined to be a Type IIa diamond. Type IIa diamonds are the most chemically pure type of diamond and often have exceptional optical transparency. Type IIa diamonds were first identified as originating from India (particularly from the Golconda region) but have since been recovered in all major diamond-producing regions of the world. Among famous gem diamonds, the 530.20 carat Cullinan I and the 105.60 carat Koh-i-noor, are examples of Type IIa 

A fine 15.08 carats Burma sapphire and diamond ring, by Bvlgari. Estimate $350,000 – $500,000. Photo Christie's Image Ltd 2015

Set with an octagonal-cut sapphire, weighing approximately 15.08 carats, flanked on either side by a triangular-cut diamond, to the circular and baguette-cut diamond shoulders, mounted in platinum. Signed BVLGARI

With report 13055036 dated 4 June 2013 from the Gübelin Gem Lab stating that gemmological testing revealed characteristics with those of sapphires originating from Burma (Myanmar). No indications of heating

With report 11005109 dated 6 December 2007 from the AGTA Gemmological Testing stating that the sapphire's origin is Burma (Myanmar). No indications of heating; accompanied by a Burma Sapphire JewelFolio No. 0001 attesting to the rarity of this sapphire

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