An important Art Deco aquamarine, tourmaline, diamond and enamel brooch, by Cartier. Photo: Christie's Images Ltd 2013

Of geometric motif, designed as an curved openwork rose-cut diamond and black enamel plaque, set with a rectangular-cut green tourmaline, accented by a rectangular-cut rubellite tourmaline, to the articulated triple staggered cascade, the center suspending a pear-shaped green tourmaline, to the rectangular-cut lighter green tourmaline and triangular-cut aquamarine link, spaced by a black enamel hoop, with a cushion-cut aquamarine terminal, accented by rose-cut diamonds and black enamel, flanked on either side by two similarly designed tassels, one terminating with an oval-cut aquamarine, the other with a smaller cushion-cut aquamarine, mounted in platinum and 18k gold, 1927, with French assay marks. Signed Cartier, France. Estimate:  $200,000 – $300,00

With certificate of authenticity no. NYC2010-9 dated 23 April 2010 from Cartier Joailliers

Christie's. MAGNIFICENT JEWELS. 15 October 2013. New York, Rockefeller Plaza.