Friday, April 3, 2009

(Cut, Clarity, Color and Carat)


The most common usage of diamonds today is as gemstones used for jewelry. When buying a diamond you should always have four factors (four Cs) in the mind. These four Cs are Cut, Color, Clarity and Carat. Majority of gem diamonds is traded on the wholesale market based on single values for each of these 4 factors. To set expected price range you need to know all four factors and consumers that are purchasing individual diamonds are often advice to use the 4 Cs in order to buy diamond that is just right for them. However although main characteristics of each diamond are described with four Cs you also need to consider some other characteristics, for instance presence of fluorescence of individual diamond and even history of the diamond (its previous owners and its source).Evaluation of gemological institute is another contributing factor that affects diamond’s price. Most recognized gemological association is Gemological Institute of America (GIA). GIA has long history in performing evaluations on diamonds because they were first laboratory in America to issue modern diamond reports and evaluations and are known for their consistency. Evaluation is very important especially when judging color and clarity because here is very much needed professional assistance and experienced eye unlike carat weight and cut angles that are mathematically defined. Among other highly judged evaluation societies are also American Gemological Society and Diamond High Council located in Antwerp, Belgium. Antwerp is the major city of world's diamond industry. So let us begin with four CS.

CARAT

As it was already mentioned, diamonds were first discovered in India. The first unit of weight that was used for the diamonds was the carob seed or to be more precise the weight of the seed from the seed pod of the carob or locust tree was equivalent to a 1,00 carat diamond. Today weight of the diamonds is measured in carats and one carat is defined as 200 milligrams.Here is important to say that diamonds weight is related but is not the same as its size because two diamonds with same shape, with equal carat weight, clarity and color that were cut from the same rough could have different size depending of proportion of each of these two diamonds where better cut diamond will look bigger than the one that wasn’t cut that good. The price per carat isn’t increasing in exact proportion with its size. Diamond prices in fact go up exponentially with carat weight because demand is much bigger for diamonds that are weighing more cause they are very rare to find. For instance doubling the carat weight from one carat to two carat will raise the price more than two times, and this is even more expressed when one diamond’s weight is under one carat and one just above one carat because the one just under 1,00 carat (for example 0,95) will have significantly smaller price than the one that is just above 1,00 carat (for example 1,05) all because of difference in demand. This is all because in average half of diamond gets lost when cutting, which means that for larger cut diamond, larger rough diamond is required and therefore the price increases most steeply with carat.In determining actual diamond’s price important role goes to Rapaport Diamond Report, which is weekly diamond price list that is published every week by Martin Rapaport, CEO of Rapaport Group of New York for different diamond cuts, clarity and carat weights. This weekly report is in fact baseline for retail-price because jewelers trade diamonds at negotiated discounts off the Rapaport Price. Phrase “total carat weight” or t.c.w. is also a much known phrase in the world of diamonds and describes total mass of diamonds in some piece of jewelry when more than one diamond is used. Total carat weight is widely used for diamonds earrings, diamond bracelets, diamond necklaces and other similar jewelry indicating the mass of all diamonds used in certain piece of jewelry.CLARITYMajority of the diamonds have internal defects known as “inclusions”. Clarity is measure of diamond’s inclusions. These inclusions can be crystals, structural imperfections or some foreign material that have as a consequence less light passing through diamond. If these inclusions are small or if there’s a few of them, more light can pass through the diamond, making it more beautiful and of course more expensive.There’s no gemstone that can produce the amount of brilliance that diamond can. Diamonds that are free of inclusions are very rare and therefore very expensive. Clarity of each diamond depends on number, size, location and visibility of inclusions.Clarity of individual diamond can be affected by two types of inclusions – External and internal. External inclusions are impurities on the surface of the diamond and the interior inclusions are impurities in the interior of the diamond (majority of internal imperfections is the result of breakage in the chemical structure of individual diamond.Gemological institute of America and other organizations have developed systems to grade diamond’s clarity. Most common is the use of hand held loupe or microscope based on the 10-power magnification which generally speaking means that any imperfection that is not visible with x10 magnification isn’t really imperfection and isn’t considered while grading diamond’s clarity.There are ten levels of grading scale from I.F which means internally flawless which is the best and all the way to the P.3-1.3 meaning heavy inclusion that are visible with naked eye. Small numbers of diamonds have good enough clarity to be used in jewelry pieces, only about 20 % of them while others are used in industry.Although most inclusion isn’t affecting diamond’s structural integrity some inclusion like large clouds or large crack can cause unwanted consequences in form of lack of diamond’s ability to transmit and scatter light and may even completely reduce diamond’s resistance to breakage.

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