A cushion-cut ruby and diamond ring. Photo: Christie's Images Ltd 2014.

Set with a cushion-cut ruby, weighing approximately 4.57 carats, within a single-cut diamond surround, to the single-cut diamond gallery and hoop, mounted in platinum, size 5½. Estimate: $200,000 – $300,000

With report CS 59556 dated 13 March 2014 from the American Gemological Laboratories stating that it is the opinion of the Laboratory that the origin of this material would be classified as Burma (Mong Hsu Type). Heat enhancement: None

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