Négligé necklace in yellow gold, platinum and diamonds

A casual necklace in 18k yellow gold (750/1000) and 950 platinum, set with 18 old-cut diamonds estimated at G/SI clarity. Nine are approximately 0.10 ct each, four are approximately 0.05 ct each, and five are approximately 0.02 ct each. Estimated total diamond weight: 1.20 ct. Length: 42.5 cm. Width: 2.45 cm. Total weight: 60.86 g. Hallmarked with an owl's head and a mascaron. Excellent condition.