Find Your Own Diamond Mine: by David Cowley

Apply around 58,000 atmospheres of pressure to pure carbon and then heat to about 2,600 degrees Fahrenheit and you will have a diamond. For millions of years microscopic plants and animals lived and died in the ancient oceans and after time these bodies turned into carbon. When tectonic plates collided with one and another, one of the tectonic plates was pushed under the other and the bodies of the microorganism, now carbon are buried under tons of rock.
With the extrema pressure and heat the molecules of the carbon are aligned forming a diamond. This process arranges the atoms in a unique Crystal structure that cause diamonds to have tighter atoms than any other substance in the world which makes them the hardest natural material known.
These diamonds were later pushed to the surface of the earths crust by volcanic action. A volcano is an opening, or rupture, in the earths crust that allows hot molten rock to escape to the earths surface and if the conditions are right, diamonds as well. Volcano's fall into three different types.
The first type is when the tectonic plates pull apart from one another. These linear features volcano's can form in the middle of continents but also occur in the oceans. It produces rift valleys that is filled when the two opposing plates move away from each other. Since carbon has not been forced into the molten rock diamonds are usually not found. An example of rift valleys are the Great Rift Valley located in the Middle East and Africa, the Mid-Atlantic Rift, and the Rio Grand Rift in North America.
The second type of volcanic action occurs when the tectonic plates stretch as they move over a hot spot or mantle plumes. The crust of the earth is melted allowing the hot magma to move to the earths surface. An example of this type of volcano's is the Hawaiian Islands. The Hawaiian Islands consists of hundreds of island and atolls that extend for 1,500 miles or 2,300 KM. As the tectonic plates moved across the hot spot volcanoes erupted and created islands. The oldest to the newest island extend from the northwest to the southeast ending with Hawaii or the big island. Prime Diamond hunting areas is found where two opposing tectonic plates collide and one is forced under the other. This will cause carbon to be pushed into the hot magma and with tons of rock on top the pressure will be extreme. As the collisions take place large mountain ranges may be formed by the wrinkling of the earths crust such as the Rockey Mountains and the Himalayan Mountain range. As cracks and fissures is formed in the mountain ranges the magma will find its way to the surface and a volcano is formed. The Volcano eruption can be quite violent such as the Mount St. Helen's explosion in North America in 1980. The Pacific Ring of Fire is a 24,850 mile or 40,000 km horseshoe shaped ring of volcanoes. It extends from Java to Sumatra to the Himalayas to the Mediterranean and into the Mid Atlantic Ridge. The San Andreas Fault in California is another example of an active collision of tectonic plates.
Named after the town of Kimberley in South Africa in 1870s, diamonds are found in a type of rock called Kimberley pipes. Kimberley pipes are formed from the cooling volcano core of magma that has found its way to the earths surface. It is believed that they are formed deep within the earths mantle between 93 to 290 miles or 150 to 450 kilometers deep and contain exotic compositions that are erupted rapidly and violently to the surface.
Red garnets are usually found in Kimberley pipes that contain diamonds. Since these minerals are in greater in quantities than diamonds, geologists look for these indicator in the regions where they suspect diamonds to occur. Most Kimberley pipes were formed between 70 to 150 million years ago but several have been found in Southern Africa that are believed to be 1600 million years old. Only 1 in 200 Kimberley pipes contain gem-quality diamonds.
In a nut shell look for the areas that tectonic plates are converging. Next find areas that have had volcanic activity in the distant past, the older the better. Find the Kimberley rock formations that the volcanoes have produced. If the Kimberley pipes have evidence of red garnets and other crystals then the possibility of diamonds is highly possible. Please remember the author and give him several handfuls of rough diamonds as a reward for the information provided here.
Happy diamond hunting.