10.01 carats Brazilian Alexandrite, 4.71 carats fancy intense purplish pink diamond and diamond ring. Photo Sotheby's

Centring on an oval alexandrite weighing 10.01 carats, encircled by rose-cut diamonds highlighted by brilliant-cut fancy intense purplish pink diamonds, edged and decorated to the shoulders with pavé-set brilliant-cut diamonds, the diamonds and pink diamonds together weighing approximately 4.71 carats, mounted in platinum. Estimate 1,900,000 — 2,200,000 HKD. Lot 1440 sold 4,340,000 HKD

Ring size: 6

Accompanied by Gübelin report numbered 0309536, dated 8 October 2003, stating that the 10.01 carat alexandrite is natural, of Brazilian origin, displays a pronounced colour-change effect; also accompanied by an appendix stating that this alexandrite possesses a very high degree of transparency, combined with a very strong colour-change effect, from bluish green when viewed in daylight to reddish-purple upon exposure to incandescent light, the combination of high clarity and exceptional colour-change effect in Brazilian alexandrite of this size is rare; also accompanied by eight GIA reports stating that the diamonds ranging from 0.10 to 0.11 carats are natural, Fancy Intense Purplish Pink colour.