A set of diamond, sapphire and emerald "en vol" jewelry, by Cartier. Photo Christie's Image Ltd 2014

Comprising a brooch, designed as a flock of circular-cut diamond birds, each with calibré-cut sapphire detail and circular-cut emerald eyes; and a pair of ear clips en suite, mounted in 18k white gold, with French assay marks and maker's mark. Each signed Cartier, brooch no. 927483, ear clips no. 923000 (2) - Estimate $30,000 – $50,000

Christie's. MAGNIFICENT JEWELS, 16 April 2014, New York, Rockefeller Plaza -www.christies.com