GEMS The DeYoung Red Diamond Is One Of The Largest Known Natural Fancy Dark Red Diamonds. Grade Of Weighs Carats. Gifted To The National Gem Collection By Mr. DeYoung, A Boston Jeweler. Originally Was Wrongly Identified As Garnet.
diamond measuring carats, rated in color as Fancy deep blue-green by the Gemological Institute of America. This stone is the only natural diamond known to the GIA to possess a blue-green hue, making it one of the rarest diamonds in the world.