Does the thought of purchasing a diamond ring overwhelm you? Don't think you know enough about certificates,inclusions, grading scales, and colors? Or do you know the basics, but need a refresher course?
A good understanding of diamonds is necessary before you begin shopping. Our guide gives you the basics --
the all-important "four Cs", a glossary of terms, special information on "fancy shapes," a Diamond FAQ & more
The "Four Cs" of Diamonds
4 Cs of Diamonds
Various characteristics of diamonds are graded and categorized by the diamond industry. Learning about diamonds is first learning about the "four Cs" of diamonds which are considered the most important grades and categories:
• Carat weight
These are the criteria jewelers use when grading diamonds, and they're the ones you'll need to understand to buy the right diamond for you.
First, don't confuse diamond "cut" with "shape." Shape refers to the general outward appearance of the diamond, (such as round, emerald, or pear). When a diamond jeweler (or a diamond certificate) says "cut," that's a reference to the diamond's reflective qualities, not the shape (or at least it should be, we have found that even some "jewelers" don't appear to know the difference between "cut" and "shape").
Diamond cut is perhaps the most important of the four Cs, so it is important to understand how this quality affects the properties and values of a diamond. A good cut gives a diamond its brilliance, which is that brightness that seems to come from the very heart of a diamond. The angles and finish of any diamond are what determine its ability to handle light, which leads to brilliance.
As shown in the images below, when a diamond is well-cut, light enters through the table and travels to the pavilion where it reflects from one side to the other before reflecting back out of the diamond through the table and to the observer's eye. This light is the brilliance we mentioned, and it's this flashing, fiery effect that makes diamonds so mesmerizing.
In a poorly cut diamond, the light that enters through the table reaches the facets and then 'leaks' out from the sides or bottom of the diamond rather than reflecting back to the eye. Less light reflected back to the eye means less brilliance.
Good Proportions are Key
Most gemologists agree that the best cut diamonds are those that follow a set of formulae calculated to maximize brilliance. These formulae can be seen in a diamond's proportions, most importantly how the depth compares to the diameter, and how the diameter of the table compares to the diameter of the diamond.
However, the variance in the proportions between an Ideal Cut and a Poor Cut can be difficult to discern by the casual observer.
Because cut is so important, several grading methods have been developed to help consumers determine the cut of a particular diamond. In general, these grades are:
• Very Good
• Fair & Poor
Which Grade of Cut Should I Buy?
Selecting the grade of cut is really a matter of preference. To make the best selection, you need to understand the various grades. Please note that the descriptions below are general guidelines.
This cut is intended to maximize brilliance, and the typically smaller table sizes of these diamonds have the added benefit of creating a great deal of dispersion or 'fire' as well. Ideal quality diamonds are truly for the person who enjoys knowing that he has one of the finest things that money can buy. This category applies only to round diamonds.
In the case of round diamonds, many Premium Cut diamonds have cuts that are the equal of any Ideal Cut diamond, though they often can be purchased at slightly lower prices than AGS Ideal Cuts. They are intended to provide maximum brilliance and fire. Like the Ideal Cut, these are also for the person who enjoys knowing that he has one of the finest things that money can buy.
These diamonds reflect most of the light that enters them, creating a good deal of brilliance. With these diamonds, the cutters have chosen to stray slightly from the preferred diamond proportions in order to create a larger diamond. The result is that these diamonds fall slightly outside of some customers' preferences in terms of, for example, table size or girdle width, though, in many cases many of the parameters of diamonds in this range will overlap with certain parameters of diamonds in the Ideal or Premium ranges. Generally, the price of these diamonds in slightly below that of Premium cuts.
Diamonds that reflect much of the light that enters them. Their proportions fall outside of the preferred range because the cutter has chosen to create the largest possible diamond from the original rough crystal, rather than cutting extra weight off to create a smaller Premium quality diamond. Diamonds in this range offer an excellent cost-savings to customers who want to stay in a budget without sacrificing quality or beauty.
Fair & Poor
A diamond graded as fair or poor reflects only a small proportion of the light that enters it. Typically these diamonds have been cut to maximize the carat weight over most other considerations.
Wondering what on earth is the diamond's pavillion? Table? Culet? The graphic and supporting text below explain the various "parts" of a diamond.
The width of the diamond as measured through the girdle.
This is the large, flat top facet of a diamond.
The upper portion of a cut gemstone, above the girdle.
The narrow rim of a diamond that separates the crown from the pavilion. It is the largest diameter to any part of the stone.
The lower portion of the diamond, below the girdle. It is sometimes referred to as the base.
The tiny facet on the pointed bottom of the pavilion, which is the portion of a cut gem below the girdle.
The height of a gemstone, from the culet to the table.
When we speak of a diamond's clarity, we are referring to the presence of identifying characteristics on (blemishes) and within (inclusions) the stone.
If you think about the incredible amount of pressure it takes to create a diamond and the fact that natural diamonds are not grown in a sterile laboratory, it's no surprise that most diamonds have flaws.
Basically there are two types of flaws: inclusions and blemishes. Inclusions refer to internal flaws and blemishes refer to surface flaws. However, in the diamond grades listed below, you'll note that none of the grades include the term "blemish" -- for the purposes of grading diamonds, all flaws are called "inclusions."
Inclusions include flaws such as air bubbles, cracks, and non-diamond minerals found in the diamond. Blemishes include scratches, pits, and chips. Some blemishes occur during the cutting processes (most often at the girdle). Diamonds with no or few inclusions and blemishes are more highly valued than those with less clarity because they are rarer.
How are diamonds graded for clarity?
Diamonds are graded for clarity under 10x loupe magnification. Grades range from Flawless (diamonds which are completely free of blemishes and inclusions), to Included 3 (diamonds which possess large, heavy blemishes and inclusions that are visible to the naked eye).
Flawless: No internal or external flaws. Extremely rare.
Internally flawless: no internal flaws, but some surface flaws. Very rare.
Very Very Slightly included (two grades). Minute inclusions very difficult to detect under 10 x magnifications by a trained gemologist.
Very slightly included (two grades). Minute inclusions seen only with difficulty under 10x magnification.
Slightly included (two grades). Minute inclusions more easily detected under 10 x magnifications.
Included (three grades). Inclusions visible under 10x magnification AS WELL AS to the human eye. We do not recommend buying diamonds in any of these grades.
While the presence of these clarity characteristics (inclusions and blemishes) do lower the clarity grade of a diamond, they can also be viewed as proof of a diamond's identity. GIA certificates include what is known as a "plot" of a diamond's inclusions -- think of it as a "diamond fingerprint." Since no two diamonds are exactly the same, comparing the uniqueness of your diamond's clarity characteristics with the plot provided on the diamond certificate offers assurance that the diamond you pay for is the same diamond you receive.
Which Clarity Grade Should I Choose?
While Flawless diamonds are the rarest, a diamond does not have to be flawless to be stunning.
In fact, until you drop to the "I" grade, a diamond's clarity grade has an impact on the diamond's value, not on the unmagnified diamond's appearance.
Diamonds with VVS and VS grades are excellent choices for both value and appearance.
More affordable (and still a great choice) are those diamonds which gemologists call "eye-clean" - diamonds with no inclusions visible to the naked eye. These diamonds are SI1 and SI2 and unless the recipient carries a 10X loupe (a strong jewelry magnifying glass), she won't see the inclusions.
As to I1-I3? Maybe when there's a diamond grade that's defined as "you can see the flaws just by looking at the diamond," nothing more needs to be said.
Okay, to be "fair" to I1-I3 -- not everyone notices visible flaws in a diamond. And not all "visible" flaws are "equally" visible -- think about the difference between dripping mustard on a starched white dress shirt and dripping mustard on a brightly-colored Hawaiian shirt (not that we think you have a lot of mustard dripping experience). Obviously, one shows up a lot more than the other -- visible diamond flaws are like that.
But if you choose to buy an I1-I3 diamond (which we don't really recommend), know that some people will look at it and immediately see the flaws -- and not just experienced jewelers.
When jewelers speak of a diamond's color, they are usually referring to the presence or absence of color in white diamonds. Color is a result of the composition of the diamond, and it never changes over time.
Because a colorless diamond, like a clear window, allows more light to pass through it than a colored diamond, colorless diamonds emit more sparkle and fire. The formation process of a diamond ensures that only a few, rare diamonds are truly colorless. Thus the whiter a diamond's color, the greater its value.
[NOTE: Fancy color diamonds do not follow this rule. These diamonds, which are very rare and very expensive, can be any color from blue to green to bright yellow. They are actually more valuable for their color.]
To grade 'whiteness' or colorlessness, most jewelers refer to GIA's professional color scale that begins with the highest rating of D for colorless, and travels down the alphabet to grade stones with traces of very faint or light yellowish or brownish color. The color scale continues all the way to Z.
Which Color Grade Should I Choose?
Diamonds graded D through F are naturally the most valuable and desirable because of their rarity. Such diamonds are a treat for the eyes of anyone. But you can still obtain very attractive diamonds that are graded slightly less than colorless. And diamonds graded G through I show virtually no color that is visible to the untrained eye.
And while a very, very faint hint of yellow will be apparent in diamonds graded J through M, this color can often be minimized by carefully selecting the right jewelry in which to mount your diamond. Keep in mind that, while most people strive to buy the most colorless diamond they can afford, there are many people who actually prefer the warmer glow of lower-color diamonds.
What is Fluorescence?
Fluorescence is an effect that is seen in some gem-quality diamonds when they are exposed to long-wave ultraviolet light (such as the lighting frequently seen in dance clubs). Under most lighting conditions, this fluorescence is not detectable to the eye. While most gemologists prefer diamonds without this effect, some people enjoy it. It's really just a matter of aesthetics.
A carat is a unit of measurement, it's the unit used to weigh a diamond. One carat is equal to 200 milligrams, or 0.2 grams.
The word "carat" is taken from the carob seeds that people once used in ancient times to balance scales. So uniform in shape and weight are these little seeds that even today's sophisticated instruments cannot detect more than three one-thousandths of a difference between them.
[NOTE: Don't confuse "carat weight" with "karat," the method of determining the purity of gold.]
The process that forms a diamond happens only in very rare circumstances, and typically the natural materials required are found only in small amounts. That means that larger diamonds are uncovered less often than smaller ones. Thus, large diamonds are rare and have a greater value per carat. For that reason, the price of a diamond rises exponentionaly to its size.
The classic diamond is, to most people, a round gem of sparkling white brilliance with a kaleidoscope of dazzling facets to entice the eye.
Yes and no. Diamonds are natural crystals of varying size and shape formed in the earth over millions of years. The traditional round brilliant diamond, though the most popular diamond shape of all, is hardly the whole story.
By the diamond cutter's art these crystals are carved into gems of spectacular and whimsical beauty. A cutter's skill will produce a diamond of the greatest size with the fewest flaws and the most brilliance.
Round Brilliant Diamonds
This shape has set the standard for all other diamond shapes, and accounts for more than 75% of diamonds sold today. Its 58-facet cut, divided among its crown (top), girdle (widest part) and pavilion (base), is calibrated through a precise formula to achieve the maximum in fire and brilliance.
An even, perfectly symmetrical design popular among women with small hands or short fingers. Its elongated shape gives a flattering illusion of length to the hand. Learn more about Oval Diamonds
An elongated shape with pointed ends inspired by the fetching smile of the Marquise de Pompadour and commissioned by the Sun King, France's Louis XIV, who wanted a diamond to match it. It is gorgeous when used as a solitaire or when enhanced by smaller diamonds
Pear Shaped Diamonds
A hybrid cut, combining the best of the oval and the marquise, it is shaped most like a sparkling teardrop. It also belongs to that category of diamond whose design most complements a hand with small or average-length fingers. It is particularly beautiful for pendants or earrings. Learn more about Pear Shaped Diamonds
Heart Shaped Diamonds
This ultimate symbol of romance is essentially a pear-shaped diamond with a cleft at the top. The skill of the cutter determines the beauty of the cut. Look for a stone with an even shape and a well-defined outline. Learn more about the Heart Shaped Diamond
Emerald Cut Diamond
This is a rectangular shape with cut corners. It is known as a step cut because its concentric broad, flat planes resemble stair steps. Since inclusions and inferior color are more pronounced in this particular cut, take pains to select a stone of superior clarity and color. Learn more about the Emerald Cut Diamond
Princess Cut Diamond
This is a square or rectangular cut with numerous sparkling facets. It is a relatively new cut and often finds its way into solitaire engagement rings. Flattering to a hand with long fingers, it is often embellished with triangular stones at its sides. Because of its design, this cut requires more weight to be directed toward the diamond's depth in order to maximize brilliance. Depth percentages of 70% to 78% are not uncommon. Learn more about the Princess Cut Diamond
This is a spectacular wedge of brittle fire. First developed in Amsterdam, the exact design can vary depending on a particular diamond's natural characteristics and the cutter's personal preferences. It may be a traditional triangular shape with pointed corners or a more rounded triangular shape with 25 facets on the crown, 19 facets on the pavilion, and a polished girdle. It is definitely for the adventurous.
Radiant Cut Diamonds
This square or rectangular cut combines the elegance of the emerald shape diamond with the brilliance of the round, and its 70 facets maximize the effect of its color refraction. Because of its design, this cut requires more weight to be directed toward the diamond's depth in order to maximize brilliance. Depth percentages of 70% to 78% are not uncommon. Learn more about the Radiant Cut Diamond
Cushion Cut Diamond
An antique style of cut that looks like a cross between an Old Mine Cut (a deep cut with large facets that was common in the late 19th and the early 20th centuries) and a modern oval cut. Learn more about the Cushion Cut Diamond
What is GIA Grading Report?
A Diamond Grading Report documents the specific characteristics of a diamond. These reports are issued by the
Gemological Institute of America (GIA), which is among the most respected organizations in the diamond industry.
GIA Diamond Grading Report
The GIA set the standard for diamond grading and gemological identification, and their grading system serves as the international gem and jewelry industry's benchmark credentials.
Diamond Characteristics Documented in the Diamond Grading Report
Shape and Cutting Style: The diamond shape and cutting style.
Measurement: Lists the diamond's dimensions in millimeters.
Carat Weight: The weight of diamond listed to the nearest hundredth of a carat.
Color Grade: A grading which assesses the absence of color in a diamond.
Clarity Grade: Clarity grade determined under 10x magnification.
Cut Grade: A grade of cut as determined by a diamond's face-up appearance, design and craftsmanship. A cut grade is available on round diamonds graded after Jan. 1, 2006.
Finish: Grades that represent a diamond's surface and facet placement.
Polish: Rating the overall smoothness of the diamond's surface.
Symmetry: Measuring the shape, alignment and placement of the diamond's facets in relation to one another as well as the evenness of the outline.
Fluorescence: Color, and strength of color when diamond is viewed under UV light.
Comments: A description of additional diamond characteristics not already mentioned in the report.
Clarity Plot: A map of the approximate size, type, and position of inclusions as viewed under a microscope.
Proportion Diagram: A map of the diamond's actual proportions.
Reading a Proportion Diagram
Proportion diagrams will typically include the following information:
Depth: The height of a gemstone measured from the culet to the table.
Table: Located at the top of the diamond, the table is the largest facet of a diamond.
Girdle: Range of girdle thickness.
Culet: Appearance, or lack thereof, of the culet facet.