So a colorless diamond rates higher on the color grading scale than a diamond ... why a 1-carat diamond is worth, say, $6,000, while a 2-carat diamond of similar quality might be worth $15,000. It’s ...

The Botswana government says the huge 2,492-carat stone is ... the "exceptional" rough diamond from its Karowe Mine in central Botswana. Lucara said it was a "high-quality" stone and was found ...