An emerald  and diamond necklace. photo: Christie's Images Ltd 2012

The two strands of thirty-three and thirty-one graduated emerald beads, measuring approximately 17.0 to 7.4 mm and weighing a total of approximately 598.71 carats, gathered by an oval-shaped bombé clasp set with emeralds in a diamond-set foliate surround, mounted in platinum and gold, 39.0 cm. Lot 31 Estimate CHF370,000 - CHF550,000

Accompanied by report no. 62002 dated 6 February 2012 from the SSEF Swiss Gemmological Institute stating that the emeralds are of Colombian origin, with minor to significant amount of oil 

Provenance: Christie's New York, 9 December 1996, lot 457 

Christie's. Jewels for Hope: The Collection of Mrs Lily Safra 14 May 2012 Geneva