Lot 293. A single-strand natural pearl, cultured pearl and diamond necklace, by Cartier. Estimate CHF500,000 – CHF800,000 ($526,187 - $841,899). Price realised CHF 557,000. © Christie's Image Ltd 2015.

Composed of fifty graduated natural pearls, and one cultured pearl, measuring approximately 13.2 to 6.0 mm, to the baguette and old-cut diamond clasp, 1920s, 52.0 cm, with French assay mark for platinum - Clasp signed Cartier Paris 

Accompanied by report no. 78587 dated 2 March 2015 from the SSEF Swiss Gemmological Institute stating that 50 pearls are natural saltwater pearls and that 1 pearl is a cultured pearl 

Christie's. GENEVA MAGNIFICENT JEWELS, 13 May 2015, Geneva