Lots 233 & 234. Two exceptional Type IIa diamonds, 16.19 and 15.09 carats. © Christie's Images Ltd 2017

Lot 233. A 16.19 carats Type IIa diamond. Estimate CHF 1,950,000 - CHF 2,250,000 (USD 1,940,958 - USD 2,239,567). © Christie's Images Ltd 2017

Set with a round brilliant-cut diamond, weighing approximately 16.19 carats, to the plain hoop, ring size 6 ½, mounted in platinum

Accompanied by report no. 1172454214 dated 17 February 2016 from the GIA Gemological Institute of America stating that the diamond is D colour, Flawless clarity, with excellent cut, excellent polish and excellent symmetry; and a Diamond Type Classification letter stating that the diamond has been determined to be Type IIa.

Lot 234. A 15.09  carats Type IIa diamond. Estimate CHF 1,850,000 - CHF 2,250,000 (USD 1,841,422 - USD 2,239,567). © Christie's Images Ltd 2017

Set with a round brilliant-cut diamond, weighing approximately 15.09 carats, to the plain hoop, ring size 6 ½, mounted in platinum.

Accompanied by report no. 6177716183 dated 30 August 2016 from the GIA Gemological Institute of America stating that the diamond is D colour, Flawless clarity, with excellent cut, excellent polish and excellent symmetry; and a Diamond Type Classification letter stating that the diamond has been determined to be Type IIa.

Christie's. Magnificent Jewels, 17 May 2017, Geneva