Blue diamonds are among the rarest gemstones on Earth, and while diamonds of other colors like yellow, pink and red are found in various places in the world, the place where most all blue diamonds are found is the Cullinan Diamond Mine, formerly known as the Premier Diamond Mine, near Pretoria, South Africa.
The diamonds range from pale, grayish blues to deep, vivid blues, resulting from small amounts of boron present when the crystal structure was formed billions of years ago. A small difference in the type of impurity in the crystal would create a different color diamond. For example, yellow diamonds are created when nitrogen, rather than boron, is present.
Some of the World’s Largest Blue Diamonds
The largest, most famous cut blue diamonds reside in museums or in the hands of private collectors or jewelers who often loan them for display. Here is a closer look at four of the world’s largest, deep blue diamonds.
- The Hope Diamond — At 45.52 carats, the Hope Diamond is not the world’s largest blue diamond, but it is one of the most famous, and the largest deep blue diamond. This stone was cut from a 112-carat piece that originated in India, and many legends of misfortune surround its long history. The stone was donated to the Smithsonian in Washington D.C. in 1958 where it is currently on display to the public.
- The Tereschenko — The early history of this large 42.92-carat, pear-shaped blue diamond is unknown, but it was acquired by the wealthy Tereschenko family of Russia, who owned sugar factories. It was sold in Paris in 1916 and was next seen at auction by Christie’s in Geneva in 1984. The winning bid went to Lebanese diamond dealer Robert Mouawad, who renamed it the “Mouawad Blue.” The stone is worth approximately $20 million.
- The Wittelsbach — This 35.56-carat stone has a royal history, and got its name when it became a “family diamond” of the House of Wittelsbach in Bavaria in 1722. For some decades in the 20th century, the whereabouts of the diamond were unknown until Belgian diamond expert Joseph Komkommer recognized it and organized its purchase by the U.S. and Belgian diamond industries. Since the mid-1960s, the diamond remained in private hands until it was sold to international jeweler Laurence Graff for $24.3 million in December 2008.
- Sultan of Morocco — Nearly the carat weight of the Wittelsbach stone, the 35.27-carat Sultan of Morocco, another blue diamond of Indian origin, was acquired in 1840 by Prince Nikolai Borisovich Yousupov of the Russian noble family of the same name. He purchased it in Europe and the stone remained in the Yousupov family for 82 years until Cartier of New York purchased it from Prince Felix Yousupov II in 1922. It was sold to a collector in 1972, and the stone has remained in private hands ever since.
Blue Diamonds Glow Under Ultraviolet Light
One unusual phenomenon about blue diamonds is that they glow “blue” when subjected to ultraviolet light. The exception is the Hope Diamond, which researchers discovered glows red, and remains red for several minutes after exposure—a phenomenon called phosphorescence. This would indicate the stone has a mixture of boron and nitrogen in its structure, and can be important to gemologists who want to identify which other blue diamonds may have come from the same source as the Hope Diamond.
Record Prices for Blue Diamonds Sold at Auction
On May 12, 2009, Hong Kong collector Joseph Lau Luen-Hung purchased a 7.03-carat, cushion-shaped, vivid blue diamond, now named “Star of Josephine,” for $9.48 million at auction in Geneva. The Star of Josephine was cut from a 26.58-carat rough stone found in the Cullinan mine in 2008.
Figured by price per carat, this sale surpassed the previous record for most expensive sale of a fancy blue diamond, which was a 6.04-carat stone that sold to Moussaieff Jewellers in London for $8 million in Hong Kong in October 2007. Also in 2007, a 3.7-carat, pear-shaped, blue diamond sold in Geneva for nearly $5 million, making it the third most expensive fancy blue diamond—per carat—ever sold.
The number of natural blue diamonds in the world may be small compared to other gemstones, but the larger-than-life histories, attention and value surrounding these magnificent, precious jewels will likely continue to grow.
Sources:
- Krawitz, Avi. “Sotheby’s Names Buyer of 7.03ct Blue Diamond.” Rapaport News. 19 May 2009. Accessed 02 June 2009. <www.diamonds.net/News/NewsItem.aspx?ArticleID=26413>
- Miller, Jeff. “Graff Buys Wittelsbach Diamond from Christie’s for $24m.” Rapaport News. 10 December 2008. Accessed 05 June 2009. <www.diamonds.net/news/NewsItem.aspx?ArticleID=24470>
- Miller, Jeff. “7.03ct Blue Diamond Sells for More Than $1M per Carat in Geneva.” Rapaport News. 12 May 2009. Accessed 02 June 2009. <www.diamonds.net/news/NewsItem.aspx?ArticleID=26358>
- “Sultan of Morocco Diamond—Famous Diamonds.” InternetStones.com: Independent Educational Database on Diamonds, Pearls, Colored Stones and Minerals. Accessed 07 June 2009. <www.internetstones.com/sultan-of-morocco-diamond-famous-jewelry.html>
- “Tereschenko Diamond—Famous Diamonds.” InternetStones.com: Independent Educational Database on Diamonds, Pearls, Colored Stones and Minerals. Accessed 09 June 2009. <www.internetstones.com/tereschenko-diamond-famous-jewelry.html>
- Thompson, Ryan. “Famous, Historic and Notable Diamonds.” The World of Famous Diamonds and Other Famous Gems. Accessed 05 June 2009. <famousdiamonds.tripod.com/famousdiamonds.html>
- Thornburg, Amanda. “UV Rays Shed New Light on the Hope Diamond’s Mysterious Red Glow.” Smithsonian National Museum of Natural History. Accessed 02 June 2009. <mineralsciences.si.edu/research/gems/hope_diamond/blue_diamond_research.html>
