Gem Guide

While not everyone will share the same opinion in what they think is beautiful in a diamond (or gemstone) most will want their gem to reflect their own taste and personality. Here are some things to consider before making that decision. You may or may not have heard of the 4 C’s which are cut, color, clarity, and carat weight. Here are explanations for each of these category’s.


Of all the 4 C’s cut has the greatest impact on the diamonds beauty. If the diamond is cut poorly, it won’t refract light well, no matter if it’s the highest color and clarity possible! The diamonds cut is maximized only when the diamond cutter, cuts and polishes it to the highest level of accuracy.

The Gemological Institute of America (the GIA) not only considers the proportions of the diamond, but also the accuracy of its overall symmetry and polish. They use the latest in technology to analyze the cut’s impact on the diamonds light performance. We suggest cut grades of Good, Very Good, or Excellent, preferring Very Good to Excellent.


Color is the next most important quality in a diamond. GIA’s grading scale starts at its highest which is D and goes right down the alphabet to Z. D is completely colorless and the most rare, E-F are colorless. Near colorless diamonds are G through J. When diamonds descend through the scale, more tint is gradually noticed. Diamonds come in various shades, most commonly yellows to browns, then they reach the fancy colors. GIA’s scale for “Fancy” colored diamonds is completely different. Contact us for more information. GIA uses the most recent lab equipment, and technology, which have met exacting standards to grade color. Remember a diamond that is graded loose, can only be assigned one color grade.


Sometimes you might hear someone compliment a friends diamond, and say “your diamond is so clear and sparkly!” You would think that’s a diamond that is way up on the clarity scale. Wrong! That’s a diamond that is cut beautifully, and is likely near colorless, or colorless. Clarity is actually the evaluation of a diamonds internal and external characteristics. GIA grades clarity at 10 power magnification. Clarity is based on the size, location, nature, number and color of the inclusions and blemishes. Then a grade of Flawless (the most rare) to Imp is given. A flawless diamond has no inclusions visible at 10 power. Some terms GIA gives to these natural characteristics occurring in diamonds are, crystals, feathers, clouds, needles.

Why should a diamond have independent lab report?

By now you have heard us mention GIA (Gemological Institute of America). Simply put, GIA has the highest standards when it comes to evaluating a diamonds cut, color, clarity and carat weight. They are an independent company who educate future gemologists, bench jewelers, appraisers and more. They also grade gems and pearls. See more at . GIA is not in the business of buying diamonds, or gems. They do not assign a value.


Carat is the standard measurement of a diamond or a gemstones weight. There are 100 points in 1.00 carat. The actual weight of a diamond can significantly impact the value. The larger the diamond, the more rare it is. The larger a diamond is, the value can increase geometrically. For example if grades of cut, color, and clarity are the same, a 2.00 carat diamond will easily cost more than twice the price of a 1.00 carat. Weight does not always enhance the value of a diamond. If a diamond is improperly cut, the added weight will reduce the brilliance. The shape of a diamond will affect its price also. Round diamonds are always the most popular, and have been for a very long time. Other shapes come in and go out in popularity, which can affect the price. What is amazing about diamonds is that while 2 stones may weigh the same, and receive the same grades from GIA for cut, color and clarity, they are never identical internally.


Contact Preusser Jewelers

If you have a diamond you would like to know more about, bring it into Preusser Jewelers. Our experienced and knowledgeable staff can tell you the cut, color, clarity, and carat of your gem and give you an accurate appraisal.

Our jewelry store in the historic Ledyard Building on the southwest corner of Ottawa and Pearl, Preusser Jewelers is conveniently located in downtown Grand Rapids and is easily accessible from both major expressways. Open Monday through Thursday from 10 to 6, Friday from 10 to 8, and Saturday from 10 to 4, Preusser Jewelers always welcomes new and returning customers.

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