Attractive natural pearl and diamond collier de chien, René Boivin. Photo courtesy Sotheby's

Composed of four strands of natural pearls, lightly graduated from 5.30 to 8.15mm, the central plaque designed as two perpendicular rows of pearls flanked with cushion-shaped and circular-cut diamonds, the clasp set with four drilled pearls framed with a pavé of rose diamonds, French assay and maker’s marks. Estimate:  140,000 – 230,000 CHF

Accompanied by SSEF report no. 69441, stating that the one hundred and eighty-one pearls were found to be natural, saltwater, and that due to the setting, the pearls on the front motif and clasp could not be tested.

Provenance: Jewels from the Collection of Odile de Richelieu, Countess Gabriel de La Rochefoucauld, Princess de La Rochefoucauld (1879-1974). This necklace was given to Odile by her mother-in-law, the Countess Aimery de la Rochefoucauld, née Henriette de Mailly Nesle (1852-1913).

Sotheby's. Magnificent Jewels. Geneva | 13 Nov 2013 - www.sothebys.com