Blue diamond

Blue diamonds are a type of diamond which exhibit all of the same inherent properties of the mineral except with the additional element of blue color in the stone. The Mohs hardness of a blue diamond is around the same as a regular diamond, with a hardness of 10. They are colored blue by trace impurities of boron within the crystalline lattice structure. Blue diamonds belong to a subcategory of diamonds called fancy color diamonds, the generic name for diamonds that exhibit intense color.