Gift of Smithsonian Gem and Mineral Collectors in 2014.
Natural (unheated/untreated) sapphire crystals from an important historic mining area in the U.S., the Rock Creek deposit of Montana, were added to the National Gem and Mineral Collection. The Rock Creek sapphires, in colors of blue, green, yellow, pink, purple, and orange, have a total weight of 451.62 carats. This collection of natural sapphire crystals of substantial size and fine color are a major upgrade to the National Mineral Collection.
