A colored diamond ring. Photo: Christie's Images Ltd 2010

Set with a cut-cornered modified square-cut fancy dark greenish gray diamond, weighing approximately 4.06 carats, to the circular-cut pink diamond prongs, gallery and half hoop, mounted in 18k rose gold, ring size 6 - Estimate $50,000 - $70,000

With report 5111019067 dated 11 August 2009 from the Gemological Institute of America stating that the diamond is fancy dark greenish gray, natural color, SI2 clarity

Christie's, New York Jewels, 15 June 2010, New York, Rockefeller Plaza www.christies.com