Natural pink diamonds are among the most valuable and rare of Earth’s treasures. Top, vivid-colored stones can bring more than $2 million per carat at major auctions. Such prices come from their rarity as much as their beauty – only a tiny percentage of diamonds have pink color, and only a tiny percentage of these have a rich, vivid color.
Research confirms that the color of 99.5% of pink diamonds comes from distortion in their crystal structure, not from trace elements, such as nitrogen, which causes yellow color in diamonds or boron, which causes blue. In pink diamonds containing nitrogen, the color is generally concentrated within parallel narrow bands called glide planes, lamellae, or pink/brown graining, depending upon the color. These lines are visible under a microscope and cutters orient them perpendicular to the table to maximize body color.