A sapphire and diamond necklace, by Harry Winston. Photo Christie's Image Ltd 2014.

Designed as a series of graduated cushion-shaped sapphires linked with marquise-shaped and brilliant-cut diamond clusters, mounted in platinum, inner circumference 36.5 cm, in black leather Harry Winston case. With maker's mark of Jacques Timey and signed Winston for Harry Winston. Estimate CHF450,000 – CHF630,000 ($511,848 - $716,588)

Accompanied by report no. 73705 dated 27 March 2014 from the SSEF Swiss Gemmological Institute stating that the sapphires are of Ceylon origin, with no indications of heating

Christie's. GENEVA MAGNIFICENT JEWELS. 14 May 2014. Geneva - www.christies.com