18 karat gold, citrine, smokey quartz clip-brooch, Herz Belperron, circa 1935; Photo Sotheby's Set in the center with a large oval citrine, framed by a tiered block of smokey quartz, maker's mark for Groëné et Darde, French assay marks. With fitted and...

Platinum and diamond clip-brooch, Cartier, circa 1925. Photo Sotheby's Of openwork geometric design set in the center with 2 old European-cut diamonds weighing 6.07 and 5.99 carats, further set with baguette and old European-cut diamonds weighing approximately...