165 - A COLOURED DIAMOND SINGLE-STONE DRESS RING The cushion-shaped diamond within four-claw setting, to a surround of brilliant-cut diamonds of yellow tint, between graduated baguette-cut diamond shoulders and a gallery of scrolled motifs, mounted in 18K gold, with case, ring size O

A COLOURED DIAMOND SINGLE-STONE DRESS RING The cushion-shaped diamond within four-claw setting, to a surround of brilliant-cut diamonds of yellow tint, between graduated baguette-cut diamond shoulders and a gallery of scrolled motifs, mounted in 18K gold, with case, ring size O Accompanied by a report from the GIA laboratory in America, stating that the cushion modified brilliant diamond weighing 4.01cts, is of Natural Fancy Yellow colour, VS2 clarity. Report number 6177430080, dated 22nd of December 2015. Condition Report: Accompanied by a report from Gemological Institute of America, stating that the cushion modified brilliant diamond is natural, weighing 4.01cts, Natural Fancy Yellow colour, VS2 clarity. Report number 6177430080, dated 22nd of December 2015 Remaining diamonds: bright and lively Stamped 750 for 18K gold Normal signs of wear, overall in good condition Total gross weight approx. 7.2g Fancy yellow diamonds are among the best known of coloured diamonds, valued for the richness and warmth of their hue. Far rarer than near-colourless stones, only around one in 10,000 diamonds displays a natural fancy yellow colour. In yellow diamonds, that co lour is caused by the presence of nitrogen within the crystal structure. As with all coloured diamonds, intensity is central to desirability, and the Gemological Institute of America grades such stones according to the strength of their hue, with the most vivid examples being the most highly prized. Among the most celebrated yellow diamonds are the Tiffany Diamond, weighing 128.54 carats, it was discovered in South Africa in 1877 and long associated with Tiffany & Co., having been worn by Audrey Hepburn, Lady Gaga and Beyoncé, and the Oppenheimer Diamond, a remarkable 253.7 carats uncut crystal from the Dutoitspan mine near Kimberley, South Africa, and now held in the col lection of the Smithsonian Institution.