Keith Penton, Head of Jewels Christie’s London comments:

“The London sale encompassed a wide variety of jewellery ranging from the mid-9th to the 21st century. Fine quality diamonds, natural pearls and signed jewels were especially sought after, exemplified by the Belle Epoque aquamarine necklace by Koch, which realised five times its pre sale estimate. Following on from the success of last week’s Hong Kong sale Chinese buyers were in the forefront of much of the bidding. The traditional Cartier section was enthusiastically received with a whimsical squirrel brooch achieving £25,000 against a pre-sale estimate of £4,500-5,500.”

A fine diamond single stone-ring by Bulgari.

The rectangular-shaped diamond weighing 14.85 carats to the tapered baguette-cut diamond shoulders and plain mount. Signed Bulgari. Estimate £350,000 - £450,000 Price Realized £758,050 ($1,095,382) (€914,966) to an anonymous.

Accompanied by report No. 1112689786 dated 9 February 2010 from the Gemological Institute of America (GIA) stating the diamond is D colour, VS1 clarity

A fine early 20th century diamond single stone-ring by Cartier.

The circular-cut diamond weighing 7.07 carats to the plain mount with single-cut diamond shoulders, 1920s. Signed Cartier, No. 4018910 (indistinct). Estimate £80,000 - £120,000 Price Realized £337,250 ($487,326) (€407,061) to an Asian Private

Accompanied by report No. 2115486123 dated 17 December 2009 from the Gemological Institute of America (GIA) stating the diamond is E colour, VS2 clarity

A natural pearl necklace.

Composed of 47 graduated natural pearls measuring 9.9 to 7.4 mm with an old-cut diamond collet clasp, clasp circa 1880, 43.0 cm long. Estimate £30,000 - £40,000 Price Realized £253,250 ($365,946) (€305,673) to an UK Trade.

Accompanied by report No. 02641 dated 18 March 2010 from The Gem & Pearl Laboratory stating the pearls were found to be natural, saltwater

A pair of diamond single-stone ear clips by Boucheron.

Each designed as a heart-shaped diamond weighing 4.73 and 4.15 carats to the claw-set mount. Each signed Boucheron. Estimate £65,000 - £85,000 Price Realized £229,250 ($331,266) (€276,705) to an Asian Private

Accompanied by report Nos. 1/20111-001 and 1/20111-002 dated 12 April 2010 from AnchorCert stating the diamond weighing 4.73 carats is D colour, VVS1 clarity, type IIA and the diamond weighing 4.15 carats is D colour, VS1 clarity, type IIA

A Belle Epoque aquamarine and diamond necklace, by Koch.

Designed as a series of graduated oval and rectangular-shaped aquamarines within rose-cut diamond Greek key surround suspending pear-shaped aquamarine drops in rose-cut diamond borders to the flowerhead spacers with detachable kite-shaped aquamarine drops, mounted in platinum and gold, circa 1905, 43.5 cm long. The clasp signed Koch. Estimate £25,000 - £35,000 Price Realized £145,250 ($209,886) (€175,317) to an Asian Private

The property of a European noble family

Notes: The firm of Koch was established in 1879 by Robert Koch, at 6 Biebergasse in Frankurt. He soon became one of Germanys leading jewellers. At some point in the 1880s, his boutique was relocated to larger premises at 56 Haus Zeil, an indication of its rapid growth. The final location, at the corner of Kaiserstrasse and Mainzerstrasse, was in a building designed by the architect Paul Wallot who also built the German Reichstag. Kochs reputation spread quickly and he became purveyor for almost all of the princely houses in Germany, and ultimately to the Kaiser, as well as to some foreign houses. To accommodate the seasonal wanderings of his clientele, he also opened a boutique in Baden-Baden. Prior to its closing in November 1987, the firm was run by Eugen Brüning.

A diamond single-stone pendant.

The heart-shaped diamond weighing 10.00 carats to the claw-set mount and fine-link chain, 37.5 cm long, with French maker's and assay marks for gold. Estimate £80,000 - £120,000 Price Realized £109,250 ($157,866) (€131,865) to an European Trade

The property of a lady.

An antique diamond riviere.

Composed of a line of 41 graduated old-cut diamond collets, mounted in silver and gold, circa 1880, 38.0 cm long. Estimate £80,000 - £100,000 Price Realized £97,250 ($140,526) (€117,381) to an UK Trade

A diamond single stone-ring.

The brilliant-cut diamond weighing 9.20 carats to the baguette-diamond shoulders and plain hoop. Estimate £35,000 - £40,000 Price Realized £73,250 ($105,846) (€88,413) to an UK private

An Art Deco brilliant-cut diamond ring.

The brilliant-cut diamond weighing 10.57 carats to the stepped baguette and single-cut diamond shoulders, circa 1935. Estimate £60,000 - £80,000 Price Realized £73,250 ($105,846) (€88,413) to an Asian Trade

A diamond single stone-ring by Cartier.

The rectangular-shaped diamond weighing 3.08 carats to the tapered baguette-cut diamond shoulders and plain hoop, in red leather Cartier case. Signed Cartier, No. 866844. Estimate £40,000 - £50,000 Price Realized £67,250 ($97,176) (€81,171) to an UK Private

Accompanied by report No. 2115542850 dated 11 January 2010 from the Gemological Institute of America (GIA) stating the diamond is F colour, VVS1 clarity

Christie's. Jewels: The London Sale. 9 June 2010. London, King Street www.christies.com