An art deco square-cut emerald and diamond ring. Photo Christie's Image Ltd 2014.

Set with a square-cut emerald, weighing approximately 6.85 carats, flanked on either side by baguette-cut diamonds, to the bifurcated half-hoop, mounted in platinum, circa 1935. Estimate $60,000 – $80,000

With report CS 39491 dated 27 February 2008 from the American Gemological Laboratories stating that it is the opinion of the Laboratory that the origin of this material would be classified as Classic Colombia. Faint clarity enhancement: Organic (Oil Type/Canadian Balsam) 

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