Lot 383. From the Estate of Lynn Wolfson. Magnificent Square Emerald-Cut Diamond Ring 21.46 carats, D color, Internally Flawless, type IIa. Estimate: 2,500,000 - 3,500,000 USD. Lot sold 3,189,000 USD. Courtesy Sotheby's

Centered by a square emerald-cut diamond weighing 21.46 carats, flanked by two emerald-cut diamonds weighing 2.02 and 2.01 carats, size 5½. 

Accompanied by three GIA reports:
No. 2155260916 stating that the 21.46 carat diamond is D color, Internally Flawless. Together with a letter from the GIA stating that the diamond has been determined to be type lla.
No. 5151262017 stating that the 2.02 carat diamond is E color, VS2 clarity.
No. 2155262021 stating that the 2.01 carat diamond is F color, VS2 clarity.

Sotheby's. Magnificent Jewels. New York | 17 Apr 2013