By Erika Winters
On November 13, 2013, Sotheby's will be auctioning the Pink Star, a 59.6-carat pink diamond, at its Magnificent Jewels auction in Geneva. According to Sotheby's, the Pink Star is the most valuable diamond ever to be offered at auction and the largest internally-flawless, fancy-vivid pink diamond that the Gemological Institute of America (GIA) has ever graded.