A coral, diamond and emerald brooch, by David Webb. Photo Christie's Image Ltd 2014

Designed as a carved coral ram's head, with marquise-cut diamond eyes, enhanced with circular-cut diamonds and a cabochon emerald, to the spiraling coral horns with sculpted 18k gold and circular-cut diamond detail, mounted in platinum and 18k gold, in a David Webb black suede envelope. Signed Webb for David Webb. Estimate $15,000 – $20,000

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