Diamond Gemstones and Jewelry

Diamond is pure carbon in a cubic crystal lattice. Because it's carbon, its chemical formula is simply C (the element symbol of carbon). Its crystal habit is octahedral and it is extremely hard (10 on the Mohs scale). This makes diamond the hardest pure element. Pure diamond is colorless, but impurities produce diamonds that may be blue, brown, or other colors. Impurities may also make diamond fluorescent. Citation