Lot 649. A Very Fine 17.62 carat Burmese 'Royal Blue' Sapphire and Diamond Ring. Estimate HK$3,200,000 - 4,000,000 ($400,000-500,000). © Phillips

One step-cut sapphire, 17.62 carats. Flanked by baguette and triangular-shaped diamonds. 18 karat white gold. Size 6¾.

(17.62-carat Sapphire)
Gübelin report, numbered 18097160, dated 14 September 2018, Burma, no indications of heating, Royal Blue colour.
SSEF report, numbered 103190, dated 5 October 2018, Burma, no indications of heating.

Note: Burma has been home to the world’s finest rubies and sapphires since ancient times, and its sapphires are particularly known for their superb, rich and vibrant blue hue, which is described as ‘Royal Blue’ in the trade. This name has since then become synonymous with sapphires of the highest caliber.
Modern Burmese mines yield very few sapphires of gem-quality, even fewer of which exceeds 10 carats after cutting and polishing. This exceptional sapphire that is free from any heat treatment weighs close to 20 carats and endowed with the superlative ‘Royal Blue’ colour, is surely the dream of gemstone aficionados.
This particular cutting style also adds to its rarity because a step-cut tends to mask the gemstone’s fire. Only roughs with the right colour saturation and crystal quality would be able to display this very luster and vivacious blue flashes in the master cutter’s hands, deeming it the ultimate collector’s stone.

Phillips. Jewels & Jadeite, Hong Kong Auction 25 November 2019