From Element To Riches
Essay by 24 • October 13, 2010 • 1,347 Words (6 Pages) • 1,401 Views
From Element to Riches
A diamond in a sense is the most communal, elegantly, used jewel used in circulation today. Do people in actuality understand the concept and edifice of this mineral? A diamond is known as the hardest rock in existence and to most of the world it is a piece of jewelry, but do we know what the chemical composition of a rock and how is it formed?
A diamond in actuality is carbon in its most concentrated form. While a few diamonds may have trace impurities such as boron or nitrogen, most diamonds are composed mostly of carbon. Carbon is a chemical that is fundamental in the process of life and used in various amounts of ways on the Earths surface. In diamonds, carbon atoms share all four valance electrons with adjacent carbon atoms, which form a tetrahedral unit. The covalent bond that is formed in this process is responsible for many of the diamonds superlative properties. As a result of the highly symmetrical arrangement of eight atoms that are fundamentally arranged in a repeating structural unit diamond crystals can form a variety of different shapes known as crystal habits. The octahedron is the most common of these crystal habits, but others include cubes dodecahedra and combinations of theses shapes. All however, are manifestations of the cubic crystal system to which the mineral diamond belongs. Diamond crystals that are real do not have entirely smooth faces which can be seen in the trigons that reflect the subtle changes of height in the diamonds face. However some raised trigons that point the same direction as the crystal face can occur from dissolution, etching, and the crystals natural growth. Another notable property that the diamond is well known for is its hardness. Diamonds are the hardest substance known, receiving a ten on Moh's hardness scale. While diamonds are not fragile or prone to breaking they can fracture or shatter. The best place for splitting a diamond is along one of its lines of cleavage as the crystal is know to have fewer chemical bonds on the plains of its octahedral face which allows for its perfect cleavage. Two of the most valued attributes of the diamond are its brilliance and luster, qualities obtained from the diamonds great ability to refract light. Light that passes through a diamond is reduced to approximately 77,000 miles per second, displaying the maximum amount of reflectance which creates what is referred to as an adamantine luster. When the light energy in the diamond equals the amount needed to change the electron configuration, parts of the spectrum are then absorbed. Pure diamonds are colorless because the visible light does not have enough energy to alter the electron configuration, meaning that no light can be absorbed. However when the diamond contains impurities such as nitrogen, boron, or hydrogen or has structural flaws electron states can be effected by the visible lights energy allowing the diamond to display colors such as yellow, blue, red, violet, real white, black, and many others.
Diamonds are poor electrical conductors due to their transparent color; they can however, be used as an insulator and in some rare diamonds, such as the gray-to-blue ones, can be used as semi-conductors. Diamonds are excellent conductors of heat though. Their capacity for heat conduction exceeds that of copper by about four times, when at room temperature. The vibrational energy travels along the strong internal chemical bonds of the crystals. Therefore the incredible strength of the diamond provides excellent thermal conduction as well.
Diamonds form in the molten rock at the Earth's mantle, about a hundred miles below the surface. In order for a diamond to form the carbon must be subjected to temperatures of at least 752 degrees Fahrenheit and under pressure of at least 435,113lbs per square inch. After being formed diamonds are brought to the surface through powerful magma eruptions that create kimberlite pipes. These pipes were first founded in Kimberly, South Africa, and it is believed that the vast majority of the eruptions occurred between 1,100 million and 20 million years ago. As magma flows through deep fractures in the Earth's crust the kimberlite pipes are formed. These eruptions are usually very short, generally being completed in just a few short hours, however, just because they are over rather quickly there strength is not to be underestimated. They originate ate depths three times that of the source of volcanoes and have many more times the power than that of the volcanic eruptions that occur today. When the eruptions occur the magma in the pipes push the diamonds as well as other rocks and minerals through the mantle and crust. The magma then cools inside the pipes leaving conical veins of bluish kimberlite rock that contains diamonds.
While all diamonds originate from kimberlite pipes geological activities such as water or erosion can move diamonds thousands of miles away from their original location. Currently diamonds are being mined in about 25 countries on every continent except Europe and Antarctica. The majority of production is from Borneo, Russia, Brazil, Botswana, Zaire, Australia, and of course South Africa, which remains the diamond leader of both volume and value.
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