Fine ruby and diamond ring. Photo Sotheby's

Centring on an oval ruby weighing 6.01 carats, surrounded by marquise-shaped diamonds together weighing approximately 2.50 carats, highlighted by circular-cut yellow diamonds, mounted in 18 karat white and yellow gold. Estimate 4,700,000—6,000,000 HKD. Lot Sold 5,660,000 HKD

Ring size: 5¾

Accompanied by Gübelin report numbered 0706528, dated 29 June 2007, stating that the 6.01 carat ruby is natural, of Burmese (Myanmar) origin, with no indications of heating. This colour variety of ruby may also be called "pigeon's blood red" in the trade; also accompanied by an appendix stating that this ruby "possesses a saturated and homogeneous colour, combined with a high degree of transparency. Such a combination of characteristics is rare in natural rubies of this size."

Ruby and diamond "Foliage' bracelet, circa 1959, Van Cleef & Arpels. Photo Sotheby's

The foliage bracelet of cross-over design set with a line of calibré-cut diamonds, edged by graduated oval and cushion-shaped rubies together weighing approximately 29.60 carats, and graduated marquise-shaped diamonds, the diamonds together weighing approximately 20.00 carats, mounted in platinum and 18 karat white gold, length approximately 170mm, signed and numbered 84059. Estimate 3,200,000—3,800,000 HKD. Lot Sold 4,460,000 HKD

Accompanied by Van Cleef & Arpels certificate of authenticity, dated 29 July 2010, stating that this bracelet is a genuine Van Cleef & Arpels item; also accompanied by Gübelin report numbered 1003669/1to34, dated 11 March 2010, stating that the rubies are natural, of Burmese (Myanmar) origin, with no indications of heating; and a signed box.

Ruby and diamond necklace. Photo Sotheby's

Composed of fifty-three oval and cushion-shaped rubies together weighing approximately 104.60 carats, each framed by brilliant-cut diamonds, linked by brilliant-cut and marquise-shaped diamonds, joined by two similarly-set stylised links, the diamonds together weighing approximately 52.60 carats, mounted in 18 karat white gold, length approximately 430mm. Estimate 1,200,000—1,600,000 HKD. Lot Sold 1,460,000 HKD

Accompanied by GRS report numbered GRS2010-072059, dated 8 September 2010, stating that the rubies are natural, of Burmese (Myanmar) origin, with no indication of thermal treatment.

Rubellite and diamond necklace and pair of matching pendent ear clips, Tiffany & Co.  Photo Sotheby's

Composed of seven graduated rubellite drops together weighing approximately 90.00 carats, supported by scrolls of brilliant-cut diamonds, length approximately 380mm; and pair of matching pendent ear clips, each suspending a rubellite drop altogether weighing approximately 20.00 carats, to a similarly-set surmount, clip fittings; the diamonds altogether weighing approximately 9.00 carats, mounted in platinum, signed and numbered 19464164 and 19464172 respectively. (2). Estimate 560,000—650,000 HKD. Lot Sold 680,000 HKD

Accompanied by a signed box.

Rubellite is a member of the family of tourmalines, and its colour glitters in beautiful nuances in the range from red to shocking pink. Exhibiting a deep intense red colour, absent of any tinges of brown, rubellite is the most valuable of tourmalines. Rubellites of high clarity and intense colour are extremely rare and exceptional. The rubellites suspending from this diamond necklace are all of uniform colour and have no visible inclusions to the naked eye. To be able to find nine rubellites whose intense colour, shape and clarity are so well matched is a tribute to Tiffany's and their pursuit towards perfectionism and producing only the highest quality jewelry.

Red spinel, pink sapphire, amethyst and diamond ring, Wallace Chan. Photo Sotheby's

Centring on a cushion-shaped red spinel weighing 9.43 carats, to a stylised mount decorated with cabochon pink sapphires together weighing approximately 3.75 carats, supported by an oval amethyst, highlighted by brilliantcut diamonds extending to the shank, the diamonds together weighing approximately 5.05 carats, mounted in titanium, signed. Estimate 400,000—500,000 HKD. Lot Sold  680,000 HKD

Ring size: 5½

Accompanied by GRS report numbered GRS2010-051637, dated 24 May 2010, stating that the 9.43 carat spinel is natural, Vivid Red colour, of Burmese (Myanmar) origin, with no indication of treatments.

Ruby and diamond brooch-ear clips, Aletto Brothers. Photo Sotheby's

Modelled as two plum flowers, the petals encrusted with calibré-cut concealingly-set rubies together weighing approximately 25.00 carats, the flower centres, leaves and stem set with pear-shaped, brilliant-cut and baguette diamonds respectively, highlighted by cabochon rubies, the diamonds together weighing approximately 8.15 carats, mounted in platinum and 18 karat yellow gold, plum flowers detachable as ear clips, clip fittings, signed and numbered 108107. Estimate 400,000—480,000 HKD. Lot Sold 620,000 HKD

Ruby and diamond brooch, Van Cleef & Arpels. Photo Sotheby's

The brooch mystery-set with calibré-cut rubies together weighing approximately 12.50 carats, outlined with brilliant-cut diamonds together weighing approximately 2.80 carats, mounted in platinum, signed and numbered N.Y. 56014. Estimate 480,000—700,000 HKD. Lot Sold 596,000 HKD

Ruby and diamond ring. Photo Sotheby's

Centring on an oval ruby weighing approximately 5.07 carats, surrounded by brilliant-cut diamonds together weighing approximately 2.30 carats, mounted in platinum. Estimate 400,000—500,000 HKD. Lot Sold 500,000 HKD

Ring size: 6

Accompanied by GRS report numbered GRS2011-011871, dated 18 January 2011, stating that the 5.07 carat ruby is natural, of Burmese (Myanmar) origin, with no indication of thermal treatment

Sotheby's.. Magnificent Jewels and Jadeite, 06 Apr 11, Hong Kong www.sothebys.com