Most of the natural diamonds that you admire in a jewelry store today were created millions, and perhaps billions, of years ago. Deep below the Earth’s surface (about 100 miles or more) the basic element of carbon was placed under intense levels of pressure and heat, and diamonds were born. The diamonds would have existed permanently in the molten rock of the Earth’s mantle, but small fissures and fractures formed in the mantle and crust and the magma, or molten rock, shot up to the Earth’s surface through these cracks. Acting just like an elevator the magma deposited diamonds, minerals and other stones along its path, and left behind what is called a kimberlite pipe.The pressures and forces of the magma reaching the surface caused an incredibly violent and powerful eruption, which left a vast crater in the surface full of sediments, volcanic rock, minerals, stones and diamonds. Kimberlite pipes were created by volcanic activity on most of the Earth’s continents and are identified by geologists and miners by the kimberlite rock that always accompanies diamonds.
Over the course of centuries some kimberlite pipes fell victim to erosion and geological activity, and many diamond sites are found in river beds and deep shafts by these natural events, but the majority of mining takes place within kimberlite pipes.
Diamonds are the hardest mineral known to man, which means it has many other uses besides jewelry. In fact approximately 80 percent of the natural diamonds mined each year are used solely for industrial purposes. Diamonds are used to cut and grind, as well as polish most hard substances. Diamonds are used in shaping or creating ceramics, stones, metals, concrete, other gems and even in some computers. Another common application is on cutting blades, from huge utility blades used to cut concrete and stone to surgical tools, a diamond’s durability cannot be beat. The incredible resistance to wear that makes diamonds so hard is another key reason that they are often selected for industrial uses.
A diamond that is spared from industrial uses will display characteristics necessary to successful jewelry production. A rough diamond will require several processes before it can make its way into the jewelry store or loose diamond merchant’s shop. First a diamond is examined for cleaving or sawing. This process will reduce larger stones to appropriate cutting size, or may turn a very large stone into several high quality cut diamonds. Special equipment and training is required for all processes of diamond processing, sawing and cleaving can even require lasers. After that a diamond is cut, or shaped, by either a hand cutting method or a bruiting by machine. This will produce the common shapes in which jewelry diamonds are sold - such as round, radiant, oval, pear, emerald or marquise. This is also the step in processing where facets are added to give a diamond more depth and sparkle. The final, finishing touch is the polishing of the cut diamond. Oddly enough it requires diamonds to polish diamonds, and a special polishing wheel is coated with diamond powder to achieve the final finished stone.
From this point a diamond may take many different paths. It may be examined and certified by a gemological laboratory, or it may be sold to a merchant as a loose stone. Either way, a diamond will need a basic assessment that is the requirement of most consumers looking to purchase a diamond. Generally a consumer all ready knows the cut and style they are seeking and will also want to know the carat size of the stone, they will need a proper assessment of the clarity and the color. Known as the “4 Cs” this method of analysis was designed by the Gemological Institute of America, and has become a standard practice when buying a diamond or diamond jewelry.
There is a global market for diamonds and in the United States the “hub” of all diamond sales is the “Diamond District” in New York City. The Diamond District receives approximately 90 percent of the diamonds sold in the United States each year. An estimated 2,600 vendors and merchants operate within the neighborhood at West 47th Street between Fifth and Sixth Avenues. Other global centers of the industry include London where there is a historic trade in rough stones; Mumbai, India which is increasing in its significance for cut stones and loose diamonds; Ramat Gan, Israel where a brisk trade in cutting and polishing diamonds is developing; and of course Johannesburg, South Africa a major historical source and home of some of the largest working diamond mining facilities.
For millions of years diamonds formed and existed in the Earth’s mantle, and cataclysmic events delivered them to the surface where they have been found, cut, polished, worn and admired for centuries. Diamonds and diamond jewelry remains an incredibly popular subject and are treasured by all who own them.
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