Bismarck Sapphire Necklace

The 98.57-carat Bismarck Sapphire is mounted in a platinum necklace designed by Cartier, Inc., set with 312 baguette and round brilliant cut diamonds and accented with 8 square-cut sapphires.The Bismarck Sapphire was originally set horizontally in a necklace designed by Cartier in 1927. Then in 1959, Mona von Bismarck had the necklace transformed into its current necklace, with the sapphire set vertically in its mounting. The magnificent sapphire exhibits the highly-prized deep blue color of sapphires from Burma. Historically the finest sapphire gems came from Burma, Sri Lanka, and the Kashmir region of India. Although sapphires occur in a wide variety of colors, traditionally blue has been the most popular and valuable. Sapphire is the gem variety of the mineral corundum. Pure corundum is colorless, but small amounts of impurity atoms can impart a range of colors. In this case, iron and titanium are responsible for the beautiful blue color of the sapphire.The necklace is named after its donor, Countess Mona von Bismarck, an American socialite who married German Count Eduard von Bismarck in the late 1930s. She donated the necklace to the Smithsonian in 1967, and it is on display in the Gem Gallery at the National Museum of Natural History.