Diamonds can be created through both geologic forces and man-made processes. However they are made diamonds have many uses. In the first part of this essay we will look at the geologic forces involved in the making of a diamond. Next we will examine the man-made processes. In closing we will take a brief look at the many uses of diamonds.
As we begin to look at how diamonds are formed it’s important to understand a little about the composition. Graphite which is used for pencil lead and a lubricant is pure carbon just like a diamond. So the hardest mineral and one of the softest share the same composition. The difference is in the bonding. Diamonds have covalent bonds that form a three dimensional structure. Graphite also has covalent bonds that form together in sheets with much weaker electrostatic bonds. These bonds also known as van der Waals bonds are what makes graphite so soft (Charles C Plummer).
Natural diamonds are formed at both a high pressure and temperature at depths of 140 to 190 kilometers (87 to 120 miles) in the Earth’s mantle. Minerals that contain carbon provide the carbon source and growth periods occur from 1 billion to 3.3 billion years. This is a significant number that represents twenty five to seventy five percent of the age of the earth. The diamonds are moved close to the Earth’s surface through deep volcanic eruptions of magma (http://en.wikipedia.org/wiki/Diamondwikipedia).
Now let’s take a closer look at the processes which move diamonds from deep within the earth to a place closer to the surface, where they can be mined. Gas-rich magmas otherwise known as molten rock, force their way up from the mantle and erupt explosively at the surface. Sometimes during this process they sweep through an area that is rich in diamonds. The flow then picks up the diamonds and carries them along toward the surface with any minerals that are nearby. As the magma cools it solidifies into carrot shaped pipes and sometimes thin dykes of kimberlite rock. These rocks are named for their place of discovery in Kimberley, South Africa. These pipes normally extend to around 2.5km below the surface. If left un mined the upper levels erode over hundreds of millions of years, exposing any diamonds they carried to the surface ((http://www.nhm.ac.uk/nature-online/earth/rock-minerals/diamonds/diamond-formation).
Diamonds may also be formed on the earth’s surface at impact sites when an asteroid strikes the Earth. When an asteroid impacts the Earth extreme temperatures and pressures are produced. These could easily equal the blast of nuclear weapons and have temperatures hotter than the sun’s surface. These high temperatures and pressures are more than adequate to form diamonds. These theories can be supported by the finding of tiny diamonds around asteroid impact sites such as Meteor Crater in Arizona. Polycrystalline industrial diamonds of 13 millimeters have been mined at Popiqai crater in Northern Siberia, Russia. NASA...