Gem-set brooch, Michele della Valle. Phote Sotheby's

The blackamoor with a carved ebony face, the turban and tunic embellished with a briolette and brilliant-cut diamonds, circular-cut rubies and peridots and a seed pearl, signed Michele della Valle and numbered, Italian assay marks, case. Lot 76. Estimate 6,500-9,500 CHF

Sotheby's. Magnificent Jewels and Noble Jewels; Geneva | 14 May 2012, 11:00 AM www.sothebys.com