This magnificent two stone diamond ring has a triangular rare blue diamond totalling 10.95 carats and is paired with a triangular white diamond that weights 9.87 carats. According to Christies Auction house in New York and the Gemmological Institute of America the diamond is the largest triangular shaped vivid blue diamond of its kind. The Bulgari blue diamond ring is valued at over $15 million. Both diamonds are perfectly matched in size and shape. The ring was first purchased in 1972 for $1 million update `wp_posts` set `post_content` = £7000,000) from Bulgari in Rome. The Bulgari blue diamond probably came from the Premier Diamond Mine in South Africa, virtually the only mine in the world producing blue diamonds.