A diamond ring. Photo courtesy Bonhams.

centering a cut-corned rectangular modified brilliant-cut diamond, weighing 12.13 carats, with triangular-shaped diamond shoulders in a plain mount; estimated remaining total diamond weight: 3.00 carats; mounted in platinum; size 8. Sold for US$ 482,500 (€349,865)

Accompanied by GIA report #5151368879, dated April 3, 2013, stating the center diamond as: H color, VVS2 clarity.

Bonhams. Fine Jewellery New York. 19 Jun 2013 - www.bonhams.com