A sapphire and diamond necklace-brooch, by Cartier. Photo Christie's Image Ltd 2013

Designed as a scrolling neckchain of brilliant and single-cut diamonds alternating with square and baguette-cut diamonds, suspending a scalloped fringe of brilliant-cut diamonds, the front set with a detachable brooch, centering upon an octagonal-shaped sapphire weighing approximately 17.95 carats, within a square and baguette-cut diamond lozenge shape border and two-tiered brilliant-cut diamond trefoil surround (with additional necklace fitting), mounted in platinum, 36.5 cm long. Signed Cartier, Paris, No. 03678. Price Realized $625,176

ACCOMPANIED BY REPORT NO. 13025197 DATED 18 FEBRUARY 2013 FROM THE GüBELIN GEMMOLOGICAL LABORATORY STATING THAT THE 17.95 CARAT SAPPHIRE IS OF SRI LANKA (CEYLON) ORIGIN, WITH NO INDICATIONS OF HEATING

Christie's. HONG KONG MAGNIFICENT JEWELS.28 May 2013. Convention Hall - http://www.christies.com