Lot 134 – A diamond single-stone ring, by Cartier. Photo Bonhams

The cushion-shaped diamond, weighing 7.04 carats, between brilliant-cut diamond shoulders, to a platinum setting, signed Cartier, numbered, maker’s mark, UK hallmark, ring size N. Estimate:  $190,000 – $280,000

Accompanied by a report from GIA stating that the diamond weighing 7.04 carats is F colour, VS1 clarity. Report number 2151532224, dated 3 July 2013.

Bonhams. Fine Jewellery. London, New Bond Street. 18 Sep 2013 - www.bonhams.com