Learning Center
Welcome to our Learning Centre. This is an introduction into the world of colored diamonds and investing. Start with the 4 C’s and move on to how to select a diamond. You might just become a diamond connoisseur in the process!
The 4 C’s
The four C’s are a set of criteria used by the diamond industry to grade and evaluate precious stones. Each criterion has its own set of precise measurements. Anyone wishing to learn about diamonds will want to begin with the four C’s. They are; carat weight, clarity, color, and cut.
Carat Weight
The value of a diamond increases exponentially with its weight. Diamond weight is measured in carats: 1 carat is equal to 0.2 grams. Because the slightest fraction of a carat can result in a significant price difference, each carat is divided into 100 points.
Clarity
Specifying purity involves taking an inventory of all the internal and external impurities of a stone. Internal impurities are known as “inclusions” while surface impurities are known as “blemishes”. The final clarity grade is usually determined by how easy the inclusions and blemishes are for the grader to see.
Below is a simplified set of definitions of various clarity grades set by the Gemological Institute of America (GIA).
IF (internally flawless): No internal inclusions visible under 10× magnification to a trained eye, but there may be some tiny external irregularities in the finish.
VVS1 – VVS2 (very, very small inclusions): Tiny inclusions can barely be seen with 10× magnification, even by a trained diamond grader.
VS1 – VS2 (very small inclusions): Very small crystals, clouds, cracks or pinpoints characterize this grade. These inclusions are not very visible and have no impact on the sparkle of the diamond.
SI1 – SI2 (small inclusions): Impurities can be seen with 10× magnification and may be visible to the naked eye.
Color
Unlike white diamonds that are prized for their lack of color, natural fancy colored stones are judged by their strength of color. GIA’s system for color-grading expresses color using the attributes of hue, tone, and saturation. Using controlled viewing conditions and color comparators, the grader determines the diamond’s color from one of 27 hues. The fancy grade describes the stone's tone and saturation with romantic names like “fancy light”, “fancy intense”, and “fancy vivid”
Below are a set of simplified terms commonly used to describe color grade.
Fancy Vivid – The strongest color saturation combined with the strongest brightness.
Fancy Intense – Very good saturation of color but less so than a vivid.
Fancy (Light) – Resembling water colors characteristically with less pronounced color than a vivid or intense, but still exuding brightness.
Rarity of color also plays a role in grading a stone. For example, pink diamonds are much rarer than yellow diamonds, and as a result are accorded more value even if it happens to be smaller in size.
Cut
One might assume that the cut of a diamond would mean the shape, but in actual fact, the term “cut” is used interchangeably between proportion, grade, and shape. When it comes to assessing a diamond “cut” refers to the polish, proportion and symmetry of a stone. For example, a well cut diamond possesses brilliance, sparkle, and allure and it is the cutter’s job to bring out the best qualities of the stone. With colored diamonds the cutter’s aim is to bring out the strongest color while maintaining the most size, brilliance and allure possible. Cut may also refer to shape as well. For example an oval shaped diamond will be called an oval cut.
There are two basic cutting styles. The first is the brilliant cut. This cut uses tiny flat cuts known as facets to create geometrical shapes like Round, Oval and Pear shaped diamonds. The second is the step cut which places facets parallel to one another to create strong clear lines and rectangular forms as seen in Emerald and Asscher shaped diamonds. The two styles can also be combined to produce even more shapes or cuts and they are referred to as Mixed Cuts such as a Radiant cut.
The following is a chart of some of the more popular cuts.
A diamond’s value is as good or poor as its cut. Since cut is so important in selecting a diamond, several grading methods have been developed to help consumers determine the cut of a particular diamond.
These grades are:
- Ideal cut
- Premium Cut
- Very Good (or Fine) cut
- Good Cut
- Fair Cut
- Poor Cut
Certification & Appraisals
Having a grading report from a respected laboratory is crucial to ensuring the quality and authenticity of the diamond you are purchasing. Having a trusted certification also means being able to identify the diamond correctly.
Guildhall ensures that every diamond comes with a report from the Gemological Institute of America (GIA). They are the diamond industry’s most trusted institute when it comes to accurately mapping and determining gemstone quality. GIA was established in 1931 and has an unparalleled reputation for being unbiased.
Certification is not the same as an appraisal. Certification maps and identifies the diamond and its quality. The appraiser will use the certification as a reference point to assess the diamond’s current replacement value. Since values of diamonds change over time it is important to have the gem appraised for replacement and/or insurance purposes. To this end it is important to use an individual appraiser and even perhaps get a second opinion. This way the purchaser can obtain a good idea of the diamond’s cash value.
Finish
Symmetry and Polish
Symmetry and polish and are significant components when it comes to the cut of a diamond. The symmetry refers to the alignment of the facets, while the polish is the actual condition or smoothness of the diamond's facets.
Poor symmetry means that the light will be misdirected as it enters and exits the diamond. Meanwhile, poor polish will leave a dull, lackluster and even a blurry finish where it will continually look as though it needs a good cleaning in order to shine.
How to Select a Diamond
There are a few non-negotiables when it comes to buying a diamond.
- Make sure you are dealing with a reputable company.
- Make sure your diamond is accompanied with certification (preferably GIA) and an independent appraisal if possible. Not a retail store appraisal.
- Find out if there is a good return policy and any other fees associated with your purchase.
At this point you should have a good idea of what to look for in a diamond and what to make sure the company provides you with when purchasing a diamond.
Now let’s select a diamond.
It is important to know your budget so that you are comfortable with your purchase. It is also important to know the purpose of your investment. If the intention is for jewelry, some concessions on quality can be made which can be balanced by the effect of a setting. By deciding on a VS or SI one could free up the budget for a larger stone. After all, nobody in public will be inspecting your jewelry with a jeweller’s loop.
When it comes to purchasing a diamond for investment it is important to know that color and clarity are key. Also, the buyer should make sure to purchase a diamond of the absolute highest quality possible to ensure return on investment. Remember, that while size does matter to an extent, it is often trumped by color. For colors such as red, blue, green and orange, size is not as important because these colors are extremely rare. Loose pink diamonds are rarer than loose yellow diamonds, so one .5 carat intense pink is more expensive than a 1 carat vivid yellow diamond.
There are many specifications to take into account, but one should also not overlook allure. Diamonds are beautiful rare objects and investors are often taken by one particular diamond over another. Beauty may not be quantifiable but it does play a large role in the selection of a stone.
Glossary of Terms
| Blemish | A clarity characteristic that occurs on a diamond’s exterior surface. |
| Brilliance | The intensity of sparkle a diamond emits through reflection and refraction of light in the face up position. |
| Carat | Measurement number for the weight of a diamond calculated into hundredths of a carat. |
| Clarity | Degree to which a stone is free from flaws. Diamonds are evaluated based on scale from “flawless” to “imperfect.” |
| Color | The saturation of color realized in a diamond. Fancy colored diamonds are graded by hue and intensity ranging from Fancy Vivid to Faint. The more intense/vivid the color, the more rare it will be and therefore desirable to investors. |
| Crown | The top part of the diamond, above the girdle |
| Culet | A polished facet positioned parallel to the table, in order to diminish damage to the point. In the GIA Laboratory, graders determine culet size face-up, looking through the table facet at 10× magnification. |
| Cut | Refers to the polish, symmetry and proportions of a diamond as it pertains to optimal light reflection. |
| Cutlet | Also spelled “culet”. A facet positioned at the tip of the pavilion where the mains come together in order to diminish the chance of damage on loose diamonds. |
| Diamond | A Diamond is a clear transparent precious gemstone completely made of Carbon atoms (Chemical Composition ‘C’) crystallized in a cubic (isometric) arrangement which has been highly compressed over millions of years. |
| Facets | Diamond facets are the smooth surface areas of a diamond which have been cut, polished and positioned at different angles which allow light to enter and reflect back from the stone. The depth and width and the uniformity of the facets control the brilliance and the durability of a diamond |
| Fancy Colored Diamonds | Gemologists measure hue, value, saturation of color and the overall consistency and allocation of color to describe fancy colored diamonds. The fancy grade describes the stone’s tone and saturation with romantic terms like “Fancy Light,” “Fancy Intense,” and “Fancy Vivid.” |
| Fancy Shape | Any diamond shape other than a round shape. |
| Finish | The end result and quality of how well a diamond has been designed, and facetted by a cutter. |
| Fire | Capability of a diamond to disperse white light up from the pavilion (bottom of a diamond) and exit through the table (top of the diamond) to reflect a spectrum of light to the viewer. |
| Flaw | Imperfections inside a diamond. Also see “Mark” Note: Gemologists use the word marks when referring to clarity as they do not like to use such terms as “imperfections” or “flaws” because by the very nature of diamonds being so rare and beautiful, such negative terminology is not accepted by industry specialists |
| Flawless | Diamond that shows no inclusions after magnifying it 10 times |
| Fluorescence | A diamond’s propensity to produce a soft colored glow when placed under ultraviolet light. |
| Girdle | Perimeter of a diamond dividing the top from the bottom. |
| Hue | The color’s characteristics. |
| Inclusion | Imperfections, or flaws, found inside a diamond. (I.e. tiny spots of white, black, or other colors, cracks. |
| Internally Flawless | A diamond that may have minor surface blemishes but is internally clear. |
| Investment Diamonds | Alternative asset that provides a reliable store of value. Rare, fancy colored diamonds provide an established return on investment. |
| Loose Diamonds | Diamonds free of settings |
| Mark | Another term for “flaws” in a diamond. |
| Pavilion | Bottom of the diamond |
| Points | Measurement of the weight of diamonds. One point is equivalent to one-hundredth of a carat. |
| Polish | The appearance of the surface of a diamond. Considered one of the markers of the value of as diamond's cut and rated as Ideal, Excellent, Very Good, Good, Fair, or Poor. |
| Proportion | A combination of a diamond's brilliance, scintillation and dispersion. Obtaining the appropriate balance is achieved primarily through proper cut proportion which include the table size, crown height and angle, pavilion depth and angle, girdle thickness and culet size |
| Refraction | A change of direction, bend of a ray of light |
| Return of Light | Also referred to as “Brilliance”. It is the degree to how bright a diamond is, and how much interior distinction it offers. This affects how much light returns to the observer. |
| Saturation | The strength or weakness of the color. |
| Scintillation | way in which light disperses off the surface of stone when moved |
| Shape | The shape in which a diamond is cut. (I.e. Emerald Cut, Princess Cut etc.). Also referred to in the industry as “cuts”. |
| Symmetry | Refers to the alignment of a diamond's facets, its flat and polished surfaces. The facets should be cut to achieve the best play of light. |
| Table | Top of the diamond which shows the light. |
| Tone | The color's relative lightness and darkness |
| Transparency | degree to which a stone is clear, hazy, or cloudy |
| Vivid Diamond | A diamond that displays a rich and intense color and hue. |
| Wealth to Wear© | Wearing and enjoying a piece of jewelry housing an investment grade colored diamond. |
| Weight | Measured in carats. |
