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.
In the late the Montana Yogo Sapphire was discovered at Yogo Gulch by a gold miner working on gravel bars on the Missouri River near Helena, Montana. Yogo Sapphires do not need the color and cosmetic boost from heat treatment.