Diamond, onyx, carved ruby and enamel jabot pin, Cartier, Circa 1925. photo Sotheby's

Old European-cut and single-cut diamonds weighing approximately 1.60 carats, further set with carved rubies and onyx beads, applied with black enamel, mounted in platinum, signed Cartier, indistinct numbering. Est. 10,000—15,000 USD - Hammer Price with Buyer's Premium:  28,750 USD

Sotheby's. Magnificent Jewels. 09 Dec 09. New York www.sothebys.com