The transformation of carbon to diamond is a process that takes millions of years to complete. This takes place 90 to 100 miles below the earth's surface when carbon, probably pure graphite, is exposed to temperatures exceeding 2,000 degrees F and pressure that is 50 times greater than the pressure that exists on the surface of the earth.
Graphite and diamonds share a common characteristic. They are both pure carbon. What distinguishes the two is their molecular makeup. Graphite is composed of layers of molecules, whereas diamonds are cubic in nature. When subjected to high temperatures and incredible pressure, graphite molecules are forced to re-align and form a cubic formation known as crystal, and a diamond is born.
- Once formed, it may take another 1,000 or more years for the diamonds to reach the surface of the earth. Molten magma transports diamonds close to the surface of the earth where the magma cools and forms veins of rock called kimberlite.
- These kimberlite veins are often viewed as an indication that diamonds may be present. Mining takes place at kimberlite sites to extract rough diamonds from the cooled and hardened magma. The presence of kimberlite itself is not an indication that diamonds are present; it simply indicates that the possibility of diamond deposits exists.
- Diamonds are generally mined in kimberlite veins, but it is not unusual to find diamonds in remote areas where they have been transported from the original site and deposited. Kimberlite veins may erode over time, causing diamonds to be carried away with silt and sediment and deposited in other areas. These areas may be some distance from the original site.
- Diamonds may also be transported from one area to another via glaciers that pick up deposits and release them in new areas. Diamonds may travel hundreds of miles before being redeposited. They may also be scattered along the pathway of the glacier. Finally, diamonds may enter streams or other water sources once they have been deposited and travel to even more remote areas, miles from their original kimberlite veins.


