Turquoise, ruby and diamond brooch, John Rubel, 1940s. Photo Sotheby's

Designed as a stylised flower, the petals set with cabochon turquoise, the bombé centre set with circular-cut rubies and a brilliant-cut diamond, smaller flowers around the edge similarly set, signed John Rubel Co, one small turquoise cabochon deficient. Estimate 6,000-9,000 CHF

Sotheby's. Magnificent Jewels, Geneva | 15 Nov 2011 www.sothebys.com