3 - Figure d'homme debout en costume du XVIIe siècle appuyé sur une épée, vers 1790-1792, Paris, Ecole nationae supérieure des beaux-arts, (c)DR

A cut-cornered rectangular-cut fancy red diamond and diamond ring. Photo Christie's Image Ltd 2014

Set with a cut-cornered rectangular-cut fancy red diamond, weighing approximately 0.69 carat, within a two-tiered circular-cut diamond surround, to the circular-cut diamond bifurcated shoulders and half-hoop, mounted in platinum. Estimate $320,000 – $420,000

With report 1152642862 dated 30 August 2013 from the Gemological Institute of America stating that the diamond is fancy red, natural color 

Christie's. MAGNIFICENT JEWELS, 16 April 2014, New York, Rockefeller Plaza -www.christies.com