A Belle Époque pearl, ruby and diamond lavallière, by Andrey, probably for Cartier, circa 1910. Estimate £10,000 - 15,000 (€14,000 - 21,000).  Photo: Bonhams.

The natural pearl and platinum chain connected by a calibré-cut ruby spacer via rose-cut diamond clasp mechanisms, suspending two seed pearl tassels of unequal length, each with a pierced cupola surmount millegrain-set with rose-cut diamonds and calibré-cut rubies, mounted in platinum and gold, maker's mark GA flanking a spray of mistletoe, French assay marks, length of tassel 4.5cm

Accompanied by a report from GCS stating that the pearls measuring from 3.0 to 4.8mm were tested and found to be natural, saltwater. Report number 5775-2120, dated 8 June 2015. Please note the seed pearls under 3mm have not been tested.

Note: Cartier commissioned a number of independent jewellery workshops to manufacture their designs exclusively for them. The maker's mark on this necklace is for Andrey, a Parisian workshop who specialised in making gem-set and platinum jewels for Cartier until the 1920s. This style of necklace is a "lavallière" - a special form of necklace Cartier produced from 1900 - which featured two conjoined pendants, usually of different lengths, ending in imaginative interlinked ends. The name alluded to the stage-name of renowned French actress Eve Lavallière, who had previously worked in a hat factory, tying ribbons and cravats called lavallières.

Bonhams. FINE JEWELLERY, 24 Sep 2015 12:00 BST - LONDON, NEW BOND STREET