Description In the Grade A, our Blue Sapphire Gemstones have a dark very saturated blue color, have a very good cut, polish and a clarity rating of Slightly Included. Our Blue Sapphire Gemstones have been subjected to traditional heat treatment. NOTE: Be sure to select the RIGHT gemstone/diamond by millimeter size only. Selecting your gemstone/diamond by carat weight is NOT ACCURATE. The best way to select the right size gemstone/diamond is to consult with a local jeweler to measure your setting or gemstone.lue Sapphire HeartBlue SapphireHeart shaped Blue SapphireA Blue Sapphire Dimensions: 4.50 mm Shape: Heart Clarity: Slightly Included Make: Very Good Symmetry: Very Good Treatment: Heat Identification: Dealer