Diamonds are among the rarest and most beautiful creations of nature.
This hardest gem of all is made of only one element: carbon. It is prized for its colorless nature and purity. Most diamonds are prehistoric – over billions of years old – and are formed deep in the Earth.
Diamond is formed under conditions of high temperature and pressure, which exist only about 100 miles below the earth’s surface. The carbon atoms of a diamond are bonded in essentially the same way in all directions. Another mineral, graphite, also contains only carbon, but its formation process and crystal structure are very different. Graphite is so soft that you can write with it, while a diamond is so hard that you can only scratch it with another diamond.
The characteristic chemical composition and crystal structure of diamond make it a unique member of the mineral realm.
A diamond is the only gemstone made from a single element: it usually contains about 99.95 percent carbon. An additional 0.05 percent may contain one or more trace elements, which are atoms that are not part of the basic chemistry of diamond. Some trace elements can affect its color or crystal shape.
The way a mineral is formed helps determine its identity. Diamond is formed under conditions of high temperature and pressure that exist only in a specific depth range (about 100 miles) below the earth’s surface. The crystal structure of a diamond is isometric, which means that the carbon atoms are bonded in essentially the same way in all directions. Another mineral, graphite, also contains only carbon, but its formation process and crystal structure are very different. As a result, graphite is so soft that you can write with it, while a diamond is so hard that you can only scratch it with another diamond.
Without any of these factors, diamond could only be another mineral. Fortunately, however, this special combination of chemical composition, crystal structure and formation process gives diamonds properties that make them exceptional.
On almost all lists of modern stones, the diamond is now recognized as the stone of April. The diamond is also a gem that commemorates the 60th and 75th wedding anniversaries.
