A Blue Beauty: 25.5 Blue Diamond Discovered

     The latest diamond discovery in the news is a rare 25.5 carat blue diamond found in South Africa's legendary Cullinan Diamond Mine.  The mine owners, Petra Diamonds Ltd., say the rough diamond is a "high-quality gem diamond of top color."  The company believes that once the rough stone is cut it could yield up to $10 million.
     The estimate is based on other blue diamond roughs found in the Cullinan Mine.  A fancy vivid blue rough stone weighing 26.6 carats was cut to an internally flawless 7.03 carat polished stone and brought $9.5 million at a Sotheby's auction in 2009.  Subsequently named the "Star of Josephine" by its new owner, it broke an auction record for the highest price paid per carat for any gemstone.  Another deep blue diamond from the Cullinan Mine was auctioned for $10.8 million last year and set a new world record per carat.
     The Cullinan Diamond Mine has been producing famous gemstones for the past 111 years.  The most famous diamond to be discovered in the mine is the largest gem-quality rough diamond ever found - the Cullinan Diamond weighing 3, 106.75 carats!  The Cullinan Mine has also produced the 545 carat "Golden Jubilee" and the 530 carat "Great Star of Africa."  The mine, northeast of Pretoria, has produced more than 750 diamonds over 100 carats and is the most important source of blue diamonds in the world.