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Roger Weller, geology instructor                     

Diamond Shopping
Gilberto Fuentes
Physical Geology
Fall 2005

                                                    Shopping for the Right Diamond


            As we all know, “Diamonds are a girls best friend”, but how much do you really know about diamonds when it comes to making that special purchase? For most of us, our first diamond purchase for a woman will probably be an engagement ring. This is a very special purchase and a little time and research should be put into it. Diamonds are composed of pure carbon, which started out as coal millions of years ago and were transformed into diamonds by heat and pressure. They took a very long time to form, so take a little time and learn about diamonds as an acknowledgement of the time that it took to form the most brilliant of all gemstones. Most of the world’s supply of diamonds comes from South Africa, Russia, and Australia. De Beers Consolidated Mines, Ltd., is the oldest and largest diamond mining company in the world. They are an illegal monopoly and cannot sell loose diamonds in the United States. They instead sell loose diamonds to 150 Site Holders 10 times a year, which then distribute these diamonds to diamond cutters around the world. De Beers controls most of the diamond industry.




            Lets get into the “Four C’s” in diamond buying. I’m sure you have heard of these “Four C’s” hundreds of times, but do you really have an understanding of what they are? The Four C’s are Carat, Color, Cut, and Clarity. Each of these parameters is used to define the quality of a diamond and each affects the reflected light of the diamond. The Four C’s also determine price and the overall look of the diamond.




            Lets first look at the diamond carat. This is the weight of the diamond. One carat is 1/5 of a gram or 200mg. Most women agree that the ideal engagement ring is one carat. Marketing tradition states that you should plan on spending two months salary, thus getting the best diamond that you possibly can within your budget. Women always say that “bigger is better”, but don’t just purchase a diamond because it is one or two carats. It could be a yellow diamond with numerous flaws. Don’t forget about the three other C’s.

            Diamond color is our next C. Diamonds range in color from clear to yellow, with clear being the best. Most jewelry stores in the U.S. use the GIA letter scale, which starts at D. Ideally you would want a diamond that was a D, E, or F, but this will be determined by the amount of money you are willing to spend. Most people will get a G, H, or I, but a J, K, or L are the most affordable. The D, E, and F diamonds are rare and expensive. Don’t consider any diamond from M-Z; these are better suited for costume jewelry and not an engagement ring. Insist on seeing the diamond a on a white background and not a black velvet background, which is a common jewelers trick for making a yellow diamond look white.

            Diamond cut is the shape of how the diamond is cut. The cuts are round brilliant, preferred by most grooms, but there are emerald cuts, the marquise, which is a football or egg shape. Then there is the Princess cut which is a square shape and also another very popular shape. The cut or shape is a personal preference and every woman has her own idea of the perfect cut, so find out which one is hers before making this important purchase.





            Finally there is Diamond clarity, which is very important. All diamonds have natural flaws called inclusions and blemishes inside the diamond. These can be tiny air bubbles, black carbon deposits, clouds, and cracks. Some flaws can only be seen under a microscope, but others are very obvious to the naked eye. Ideally you want a diamond with zero inclusions, but the fewer the inclusions the more the cost. Most jewelers use the GIA scale for grading these flaws. Diamond clarity has a huge effect on the price. The scale runs from Flawless to I3. Diamond in the VS2, SI1, and SI2 are typically the ones that you and I can afford, which have very slightly included inclusions, which are hard to see in a 10x loupe.

            As you can see there is a lot more to buying a good diamond engagement ring for the very special girl. Take the time to learn about diamonds before hitting the stores. There are now ways of getting rid of inclusion, which make the diamond less valuable and can only be detected by a trained jeweler, so “buyer beware”. Here’s wishing you a happy engagement. Take care.