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The Four Cs

If you are about to embark on a mission to find the diamond of her dreams, you will encounter the phrase "four C's." The four C's are cut, color, clarity and carat (weight). These four quality indicators of diamond value have been central to diamond buying for close to a century. The oldest written mention of the four C's was in a Supreme Case from Kansas published in 1911. An expert witness testified that the value of a diamond was based on its weight, clarity, color and quality of cut. Today, the four C's remain the principal criteria for diamond value. What do these four C's mean to diamond buyers and diamond experts worldwide?

The weight system used internationally for gemstones expresses weights in carats. Carats - not to be confused for karats, a weight for precious metals - has a long and interesting history. Originally, beans from the carob tree were used for weights since they were very close in weight regardless of what seed or plant was used. This crude seed standard was eventually replaced with weights based on a gram around the year 1913. Unlike the scale illustrated, a portable jeweler's scale circa 1800, weights had to be precise.

Today one carat is equal to two tenths of a gram, in other words 1 carat is 0.2 grams.

A carat is usually expressed in decimals or a fraction. For example, a ¼ carat diamond may weigh 0.25 carats. Keep in mind that carat weights expressed in fractions are really a range not an exact weight, thus a ¼ carat diamond may weigh anywhere from 0.23 to 0.29 carats. Another way to state 0.25 carats is to state it as 25 points.

One hundred points equals one carat. Returning to our gram equivalent of one carat equaling 2 tenths of a gram, one point equals one two thousandths of a gram! It will probably be the most money you will spend to acquire something by weight. For example, if you acquire a one carat diamond that is $10,000 per carat, it will be $100.00 per point. If you have not already pulled out your calculator, the price per gram is a mind boggling $50,000 per gram.

The jewelry trade uses some standard abbreviations for weights and quality. Carat is abbreviated as "ct." or "cts." if it is plural. Points, likewise, is abbreviated as "pt." or "pts." For all the stones in a piece of jewelry, total weight is abbreviated as "twt." If a receipt states 0.53 cts., then you know it is 53 points or ½ carat.

If you have frequented jewelry stores, you may be under the impression that diamonds are not really rare. After all, there seems to be an abundance of them. To extract a carat of gem quality diamonds from a mine that is known to produce diamonds, thirteen dump trucks of dirt are removed. Not just any dirt but dirt from a mine known to produce diamonds. That carat of diamonds is usually small diamonds - the kind that surround a bigger diamond. To locate a diamond crystal big enough to fashion into a carat diamond, 50,000 pounds of dirt must be mined. The larger the diamond, the more that needs to be removed. Diamond mining involves the most removal of dirt in ratio to the ore being mined than any other type of mining in the world.

Diamonds, since a time long forgotten time, have been graded for clarity. Although today more than one clarity grading system exists, the most common is the one taught by the Gemological Institute of America (GIA) and another favorite system by the American Gem Society (AGS).

A diamond grading report, so-called a "cert" by most, is also subjective.

The process of grading a diamond is subjective. For that reason, many diamonds are purchased with a laboratory report. Keep in mind that these "certs," as they are commonly called, are also subjective. Different laboratories have slight to major differences in grading standards. In other words, the same diamond may receive a different clarity grade from different laboratories or even within the same laboratory. Use information from a "cert" as a guideline and not as gospel. Your best bet is to seek the help of a trained professional that you trust to assist you in acquiring your diamond. That is why Arthur Groom and Company has taken the time to assemble a full gemstone grading and testing laboratory and trained staff.

A few technical facts before we explain the clarity system. Magnification is standard at 10x. The "x" represents "times." This means ten diameters of magnification. A diamond measuring 5 millimeters in diameter will be 50 millimeters in diameter under 10x magnification. Location of the inclusions has influence over the clarity grade conclusion. An inclusion in the heart (middle) of a diamond will affect the clarity greater then the same inclusion on the edge of a diamond. Inclusions are inside a diamond and blemishes are located on the surface of the diamond but sometimes extending into the diamond. Many people are under the impression that diamond's black spots are carbon. Technically they may be but usually are not. Diamonds are almost pure carbon. Inside a diamond may be crystals, needles and other mineral inclusions trapped when the diamond was formed. Rarely are these inclusions composed of carbon. The best approach is to not call them "carbon spots." Jewelers who have not availed themselves of a gemological education tend to refer to dark spots as "carbon spots" instead of calling them inclusions.

Let us start at the lowest clarity and work our way up.

• I1 through I3

The clarity grade of "I" basically involves diamonds with imperfections that may affect beauty, brilliance or both. It is subdivided into three categories marked by numbers. The best of this category has a one and the worse is designated a three. Therefore, I1, I2 and I3 are the grades - I3 being the lowest grade. Although some diamonds probably deserve a grade below I3, there simply is no such grade. A rule of thumb is that if you can see inclusions or blemishes, it is probably an "I" clarity grade.

• SI1 through SI2

This group involves diamond with inclusion that may or may not be visible without magnification. The "S" stands for "slightly." Thus, these are termed "slight imperfect." Like the "I" grades, the one is better than the two. Therefore, SI and SI2 are the grades. Although you may be able to see a prominent inclusion in an SI2 graded diamond, the usual rule of thumb is that you need to observe the diamond in a face-down position rather than a face-up position to see its inclusions. You may encounter an SI3 grade. This grade, invented by the European Gemological Laboratory is a grading system used by them and it does not follow GIA standard of clarity grading.

• VS1 through VS2

These are the "very slightly imperfect" grade of diamonds. The "I" representing "imperfect" has been dropped to abbreviate the clarity term. Following the common thread, the one is best and the two is less of a grade. Starting with this grade level, the use of magnification will be needed to observe inclusions or blemishes. Position, number and darkness of the small inclusions will determine the level within this grade.
• VVS1 through VVS2

You may have already guessed that the letters stand for "very slightly imperfect." If you did, then you would be right. Once again, the numbers follow the other clarity grades and further serve to fine tune the grading steps. These inclusions are very minute and may only include a pinpoint under magnification. Two pinpoints of a white to colorless tint might be the lower level.

• FL and IF

Actually, there are two grades of flawless. One is reserved for diamonds that have no flaws internally or externally. That one is Flawless or FL. The other grade of flawless allows some very minor blemishes on the diamond but it has to be internally flawless. That grade is Internally Flawless or IF. What is interesting to note is that GIA teaches gemologists to not use the term "flaws" when referring to inclusions and at the same time promotes a grade of flawless. We agree that nature does not flaw a diamond but leaves natural mineral bits as inclusions.

Now, all you have to do is reverse these grades and their explanations and you have the usual way they are explained.

What is the color of pure water? Actually it is colorless. Color grading a diamond is really a matter of judging how near or far the diamond is compared to a colorless state. Color, therefore, is really a tint and not a color, such as white. Yes, there exist diamonds with an actual body color, such as blue, green, brown and other hues. With most diamonds, color is a term relating to the presence or lack of a tint. This tint is caused by traces of impurities within the carbon framework. For example, nitrogen dispersed at one part per million in a diamond causes the yellow tint in diamonds.

The highest color grade group is colorless. Gemologists using the Gemological Institute of America (GIA) color grading system state a color grade as a letter, such as "D." Other color grading systems for diamonds have numbers (American Gem Society) or terms (European systems). Charts are available to approximate the equivalency of these systems but for our needs, only the GIA system will be detailed.

However, other tints do exist. Grading tint is the same regardless of the hue unless the hue dominates. In such a case, the diamond may be classified as a fancy color and is graded differently.

The colorless color group consists of D, E and F. As a rule of thumb, an un-mounted diamond in both the face-up position on a white background (the way you see a diamond when it is mounted) and its face-down position (with the bottom facing up), should show no tint if it is colorless. Of course, there is some tint or there would not be three colorless grades.

The near colorless group consists of G, H, I and J. As a rule of thumb, an un-mounted diamond in the face-up position will not show a tint and in its face-down position, will have a slight tint. A diamond with a J color grade may or may not show a slight tint when one views it in a face-up position. Both the size and the cut may enhance or damper the tint. Consider this a "break-over" color that may still satisfy those who seek diamonds with no visible tint. The color of the prongs that touch the diamond may also have an effect on your ability to see a tint. It is probably best to use white gold or platinum prongs to secure the diamond to avoid intensifying the barely visible tint of a near colorless diamond. An added advantage to using white gold or platinum prongs is they are harder than yellow gold - that translates to longer lasting.

Diamonds with a color grade lower than J are not rejects. These diamonds will display a slight tint in both the face-up and face-down positions. A "warm" appearance best describes their look. Depending on the size and metal securing them, these slightly yellow diamonds can appear rather like better color grades. If budget is your concern but you want size, acquire a K or L color graded diamond and have it mounted in such a manner to enhance its color.

Can the average consumer color grade diamonds? It takes training and equipment to color grade diamonds properly. The steps between color grades are extremely subtle. Therefore, it is perhaps the most subjective of the diamond grading steps. What makes the process even more subjective is that the color grades are not clearly divided into steps. They are ranges with subtle borders. Imagine a skyscraper with a solid side of glass windows. The window in the far most left-hand side is a D. The next window is an E and so forth. Each window is graduated in tint. Therefore, within the G glass, the left-hand side has less tint that the right-hand side has - even though the entire range is a G. Now imagine that there are no actual panes between the glass panels but they abut against each other in a seamless manner. Now reduce the glass side of the building to the size of a set of perhaps five ½ carat sized diamonds - that would make a nice master diamond grading set. Can you now imagine the difficulty? To say the least, color grading is part science and part art, with a mixture of experience and training. An untrained grader who accidentally drops a diamond master set used for grading diamonds will find it difficult to rearrange them back in order.

If you select a diamond for your engagement ring that is H in color and the ring has accent diamonds of D color, the side diamonds will serve to accentuate the H color. In other words, it will be easy to see. Goldsmiths that are savvy can alter the gold work to overcome this concern. As a rule of thumb, select accent diamonds that are equal or less than the color of the center diamond.

Understanding cut grading in diamonds is like learning to drive a car with a standard transmission. Using a clutch takes time to master and so does cut grading. You do not need a degree in rocket science to determine if a diamond is well cut. Your informed impression of the diamond's brilliance and fire can be as accurate as scientific instruments for general buying purposes. We want to add to your knowledge of diamond cutting and proportioning beacuse the diamond's cut is the most important determiner of the optical performance and beauty of the diamond.

Over several hundred years, diamond cutters have developed by experimentation and cut-and-try the best angles and proportions for each style and shape of diamond. Yes, cut grade refers to proportions and not the actual shape. For example, a pear brilliant cut diamond is a shape and style of cut. Its cut quality may be impressive, and then again it may be as brilliant as a block of ice.

We are focusing on the round brilliant cut style because it has evolved as the most popular way to fashion the diamond for maximum brilliance, fire and scintillation.

Proportions are usually measured by diamond graders by using instruments. The measurements, including angles and percentages, are then analyzed to render a cut grade. To understand these proportions, one must know what the various parts of a diamond are called. The top flat facet (facets are the flat, polished surfaces of a diamond) is called the table. It is an octagon (eight sided). Surrounding the table are eight small triangle shaped facets called star facets. Next on top are sixteen facets called upper-girdle facets. We have described what diamond experts call the "crown." The crown is the face-up portion or top of a diamond.

The edge of the diamond is called the girdle. This may or may not have facets.

The lower portion of a diamond is called the pavilion. It has sixteen upper-girdle facets near the girdle. It has eight pavilion mains that extend to the point. That point is called a culet. It may actually be a point or it may be a small facet.

What makes a round brilliant cut diamond beautiful is its ability to capture light and color and redirect it to the viewer. A well cut diamond, in addition to the above ability, gathers light and color from a broad range of light sources but avoids directions where there is usually an absence of light. Think of a diamond like a ballroom crystal that takes in everything in the surrounding area and then blasts it back at the observer in stereo. You see colors, bright light and dancing flashes of reflected light all blended into a pleasing effect rather than a spot light appearance. The diamond was not always that spectacular. It started out as a crystal that did not display even the slightest spectral splendor.

Do not assume that any diamond that is not ideal cut is to be rejected. Quite the contrary, almost all diamonds not considered ideal cut are beautiful and do a fine job of dazzling onlookers in favorable lighting situations. In fact, some people cannot see the difference between an ideal cut and non-ideal cut diamond in showroom lighting.

When a diamond crystal is cut to maximize weight - an important factor affecting price - the result is a less than ideal cut diamond. To cut an ideal cut diamond, the resulting diamond will be the smallest (thus weighing the least) diamond from the crystal. In other words, to cut the best cut means the diamond cutter must lose more weight than to cut a commercial or poor cut diamond. Wow, that means you have to pay more per carat to get quality cutting! Think of it like purchasing a steak at the super market. If you want it without the bone and fat, it will weigh less. That translates to paying more per pound. If you do not mind trimming the bone and fat off yourself, then you will pay less per pound. Either way, the grocery store has to make the profit and they price the two steaks accordingly. However you cannot trim off the extra weight on a diamond to get to the idea cut inside the poorly cut diamond. It is better to pay more per carat and get a better looking diamond to enjoy for the rest of your life.

Does the ideal cut diamond look smaller than the one they could have cut from the same crystal? Diamond cutters first take a diamond crystal - usually in a form called an octahedron - and round it. Since an octahedron is like a four sided pyramid onto of another four sided pyramid, knocking off four corners makes it ready for cutting. This is the point when a cutter can decide to fashion and ideal cut or a commercial cut diamond. Either way, the diameter has been determined mechanically from the rounding-up process and that diameter does not change. For example, if a 0.98 ct ideal cut is the result, it will have the same diameter of the heavier 1.10 ct. commercial cut diamond. That means they will look the same size to your eye even though they are different weights.

However, for those who want a well proportioned diamond, here is a new way to judge the diamond you are considering. We were fortunate to have Mr. Cowing of ACA Gemological Laboratory, a well-known researcher in diamond cut who photographed the ideal cut diamond in the illustration, to provide us with a new perspective on diamond cut performance. Here is a mini-summary of this new perspective.

A diamond cutter's goal, when striving for an ideal cut diamond, is to make the diamond look the best it can to the eye of the observer. Ideal cut diamonds are fashioned to do two things - yes, there are others things involved, but let us keep this simple.

Common sense tells us that without light a diamond will not be able to perform, regardless of the quality of cut. The goal is to cut a diamond so it can provide top performance in various commonplace lighting situations.

In any lighting environment, ideally a diamond would avoid any light source that is poor. If a diamond were to use a poor light source and transmit it to you, you would see an equally poor dazzle of brilliance and fire. On the other hand, it a diamond is cut to draw from a strong source of light, you will experience a noticeable display of brilliance and fire. Where do poor source of light exist? Any light below a diamond's girdle (the edge), that is the pavilion, would not be a serious source of good illumination. After all, when placed in a ring, a diamond's best source of light is not your fingers, the dark inside of the ring and floor, is it? What about the second poor source that is to be avoided? Unless you have a very bright face, that would also not make a good source of illumination.

Believe it or not, these logical and provable facts are not what the majority of gemologists were taught. They will tell you that the darkness in a diamond is caused by light leaking out the back. For evidence, they will show you a chart showing the light paths leaking out the pavilions of deep and shallow cut diamonds. To be accurate, the diamonds would have to be cut at extremes - as illustrated in the short article on cut. Diamonds, even poorly cut diamonds rarely are cut to such noticeable proportions. The latest testing shows ideal cut diamonds draw from rich light sources and simply avoid the two obvious poor sources.

You want to observe your diamond in various settings. The strong and purposeful lighting found in jewelry stores will tend to make almost every diamond look good, even ones poorly cut. You want a diamond that will dazzle you and your friends somewhere besides the jewelry store. Therefore, do not be afraid to ask to see the diamond in various locations always from the show cases. Also, try viewing the diamond in poor light situations - like when you block the showroom lights with your hand. Does the diamond outperform the others in such a poorly lighted situation?

Brilliance is classified as the white light returned by a diamond. Brilliance is returned through the diamond's table. Dispersion, on the other hand, is the spectrum of light returned to the viewer - also called fire. The fire in a diamond is usually returned through the crown facets (facets on the top of a diamond other than the table). A well cut diamond, such as the American ideal cut, will provide a balance of brilliance and fire. However, keep in mind that the diamond will display more brilliance when it is exposed to lighting that promotes brilliance. That same diamond will provide more fire if the light source promotes fire. In other words, the light source will also play a part in the balance between the amount of brilliance and fire displayed. that is the reason for viewing a diamond under different lighting conditions. Mutiple pinpoints of light casue fire to dominate. This is exactly what jewelry stores' lighting is, spots of light in different locations. Therefore, you can expect fire to dominate your diamond in a jewelry store. You will want a broad, white light source to see how that same diamond's brilliance performs.

Avoid dark centered diamonds in normal light. These diamonds are often called "nail head" diamonds in the jewelry trade. They have been cut to collect light only from your face and what you are seeing is the poor light from your face. That is why they appear dark or grey. These same diamonds exhibit their best when the source of light is directly overhead. Unfortunately, your face is what is supposed to be directly overhead.

Ideal cut diamonds are also cut to maximize the light sources they are designed to use. Dispersion (fire) and brilliance (white light) are both emphasized for your viewing pleasure. Does this mean that you should only purchase an ideal cut diamond? Absolutely not because many non-ideal cut diamonds are simply stop-you-in-your-tracks diamonds. You need to let your eyes tell you what you want. Of course, if you are interested in learning more of the details of diamond cut that a gemologist uses to make their determinations, contact us for an appointment.

Although it is accepted that there are only four C's, we feel that a fifth C should be discussed. That C stands for "certificate." Aside from the subjectivity of diamond grading, the fact is, some laboratories grade more lenient than others.

If a diamond grading report declares a diamond to be F VS2, odds are that very same diamond may achieve and even higher grade consistently when submitted to another laboratory - or the reverse depending on how strict the first laboratory is.

Our advice is to not buy a diamond solely based on the certificate. You are playing "cert" roulette if you do. You need to enlist the assistant of a professional gemologist to walk you through the subjectivity issues. Additionally, you will find that certain laboratories have solid reputations and other are not relied upon by members of the trade. This is yet another reason to work only with a trusted retailer.

If you are considering on mail-ordering a diamond over the Internet, keep in mind that there can be some serious problems involved. Firstly, you have to front money in order to even look at a diamond. You are going to discover that some diamonds you want to see are not available. Finally, when you narrow down your choice to a few available diamonds, you can afford to see only one. When it arrives, you will have no other diamonds to compare it to. Odds are, the seller does not even handle the transaction but merely requests someone else to drop-ship the diamond. To enlist the assistance of a professional will involve a professional fee if you want the diamond examined. If you return the diamond, you will probably pay a restocking fee, postage and insurance and wait again for another diamond to arrive.

Using a retailer you trust to assist you in acquiring the diamond you want, you can have a selection to choose from. You do not have to pay up-front for a diamond merely to check it and you do not have to pay any return charges. You do not have to wait as long as two weeks between each selection. Best of all, you can ask questions and look straight into the eyes of the retailer. In today's competitive world, Internet diamonds are not much of a savings over most retail jewelry stores and often are matched in pricing. Can you really accept that less than a few cents a day is worth sacrificing your personal security by not knowing if you were duped? It is your choice, to mail order or select that important diamond from your trusted jeweler.

I do not believe that someone can study websites on the Internet, read books from their local library and gain enough knowledge to become a knowledgeable buyer of diamonds. For example, you study and carefully purchase a diamond. You decide to get a second opinion and make an appointment with a qualified and disinterested gemologist. Suddenly you discover that the diamond has a strong blue fluorescence that will make it appear oily when you are in office type lighting. Or perhaps, you learn that the cutter made an edge too thin for safely setting a prong on it.

A gemologist worth their salt may disagree with the laboratory report. Keep in mind that the laboratory report is not a test for you to see if the gemologist knows what they are doing, it is merely another opinion. Let the gemologist do their job and then ask questions, decide if their advice is sound by what they tell you and make a decision.

We look forward to helping you understand this maze called diamond buying so your diamond acquisition will be a life long pleasure.

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