A Sapphire, Yellow Sapphire and Diamond Necklace, by Cartier. Photo: Christie's Images Ltd 2013

Suspending a staggered fringe of cushion and rectangular-cut sapphires and yellow sapphires with circular-cut diamond accents, to the circular and marquise-cut diamond neckchain, mounted in gold and platinum, 1957, 15 ins., in a Cartier red leather case. Signed Cartier. Estimate:  $400,000 – $600,000

With report CS 56331 dated 12 August 2013 from the American Gemological Laboratories stating that it is the opinion of the Laboratory that the origin of the blue and yellow sapphires would be classified as Ceylon (Sri Lanka). No gemological evidence of heat

With Certificate of Authenticity from Cartier

Christie's. MAGNIFICENT JEWELS. 15 October 2013. New York, Rockefeller Plaza.