The Mackay Emerald is the largest cut emerald in the National Gem Collection and is set in a pendant of diamonds and platinum designed by Cartier, Inc. The Art Deco style necklace was a wedding gift in 1931 from Clarence Mackay to his wife, Anna Case, a prima donna of the New York Metropolitan Opera from 1909 to 1920. The emerald weighs 167.97 carats and is set in platinum with 35 emeralds and 2,191 colorless round brilliant and step cut diamonds. Mrs. Anna Case Mackay bequeathed the necklace to the Smithsonian in 1984.
Tortum Lake, posted earlier: