Diamond is an allotrope (different form) of carbon.
The word diamond comes from the Greek word "adamas", meaning "unconquerable".
The atomic structure of a diamond gives it the property of being the hardest substance known to man, natural or synthetic. The carbon atoms in diamonds are arranged in a strong, tetrahedral structure.
Diamond is the hardest natural material known and is often used for industrial cutting and polishing tools.
The diamond is thousands of times harder than corundum, the next hardest substance from which rubies and sapphires are formed. Even after many years of constant wear, diamonds will preserve their sharp edges and corners when most other stones will have become worn and chipped.
Diamond is the best known thermal conductor (heat transfer) among naturally occurring substances.
Under the normal pressures and temperatures we experience on the Earth’s surface, diamonds are actually thermodynamically unstable, slowly transforming into graphite. But diamond owners do not need to worry because it’s a process that is far too slow for humans to notice.
Most of the Earth’s natural diamond deposits are found in Africa.
Around 26,000 kilograms of diamonds are mined around the world every year. They are worth billions of dollars to the powerful companies that control their production.
Diamonds have often been a source of conflict and controversy, the term 'blood diamond' refers to a diamond mined in an unstable area and sold to finance war. This issue was brought to public attention in the 2006 movie named Blood Diamond (starring Leonardo DiCaprio and Jennifer Connelly).
Diamonds are valued according to their cut, color, carat and clarity.
Naturally occurring diamonds are formed over billions of years under intense pressure and heat. They are often brought to the Earth’s surface by deep volcanic eruptions.
The technology for synthetic diamonds was researched in the 1940’s and the first synthetically created diamond was produced in the 1950’s.