DIMONDS Diamond is the best known gem. It is known as the “king of gems” for its brilliance and for being the hardest mineral on earth. (Foa, p.50) Its characteristics enable it to be used for many different purposes. Since diamonds are the hardest gems on Mohs’ scale, they make useful tools for industrial purposes, such as drilling hard materials. However, they are quite rare, which makes them very valuable. Their beauty and brilliance make them perfect for jewelry. Diamond is made up of carbon. Another form of pure carbon is graphite. Graphite is the stable form of carbon, found at the earth’s surface. Despite the fac