Diamonds have been mined on a mass-production scale for many years and there are in total 35 countries in the world where sizable diamond stocks have been found. Diamond is only found in Kimberlite which is a volcanic rock.
Volcanic activity brings the Kimberlite which holds the diamonds nearer to the surface of the earth and this in turn means that diamonds are only found in areas where there is, or has been, significant volcanic activity in order to bring the diamond up. Although Africa has a reputation for being the most productive diamond producing region, it is actually Russia who leads the world in terms of diamonds mined per year. The major areas of diamond mining are: Africa, India, Russia, South America, Australia, China, United States and Canada.
The actual process of diamond formation is due to extraordinary levels of pressure and heat applied over a period of millions of years. This pressure and heat forces carbon atoms to form a covalent bond and then arrange themselves into what is known as a diamond lattice (essentially a grid of interconnected atoms). This structure is incredibly strong, as evidenced by it’s rating of 10 on the moh scale of hardness, and is what leds diamonds there usefullness in industrial applications requiring exposure to high levels of pressure and heat. The majority of industrially used diamond are mined in Australia in the Western Areas, most notably Argyle.