Sotheby\u2019s has a name for selling the most exquisite gems ever on earth. And this time it brings to connoisseurs a rare and almost unbelievably beautiful blue diamond that has come up for sale for the very first time in the last 300-years! Known to be a royalty\u2019s favorite up until now, the sparkling wonder will be auctioned at Geneva on May 15th.\r\n\r\nChristened as the Farnese Blue, the precious diamond bears a pear-shape with an astounding 6.16-carat. It was first excavated from the mysterious Golconda mines of India, and was originally owned by Queen Elisabeth Farnese of Spain, who received it as a wedding gift in 1714. She then passed it on to her son Philip who further conceded it down the family tree until it was owned in heritance by Maria Anna von Habsburg, wife of Elias of Bourbon, duke of Parma till 1940. After thus travelling from France, Italy and Austria over the last three centuries, the stone is finally up for grabs.As per Philipp Herzog von W\u00fcrttemberg, chairman of Sotheby\u2019s Europe and managing director of Sotheby\u2019s Germany, \u201cWith its incredible pedigree, the Farnese Blue ranks among the most important historic diamonds in the world.\u201d Estimated to sell for an estimated price between $3.7 million to $5.3 million, the gem will first be displayed in Hong Kong, London, New York, Singapore and Taipei, before arriving at the Magnificent Jewels and Noble Jewels auction in Geneva.