Every diamond is unique, and there are a variety of factors which affect the price of a diamond. How to Choose a Diamond – What you need to know:
Focus on those factors most important to you, and choose a diamond that satisfies your individual standards for beauty and value. This might be a very different diamond than someone else with a similar budget would choose.
Diamond Grading: What Qualities Matter Most?
The Four “C”
Cut – The most important property.
Color – The second most important property.
Clarity – The third most important property, provided the grade is “SI” (Slightly Included) or better.
Carat – The least important property
One of the hardest properties to judge, the cut is nevertheless the most important. Choosing a well-cut diamond requires paying careful attention to a few key characteristics
Brilliance refers to the total amount of light returned by the gem.
A cut gem’s pavilion facets should act as mirrors, reflecting the light entering the stone back to the observer. Diamonds have a high refractive index, which contributes to their great brilliance. However, the cut plays a critical role.
The angles at which a diamond is cut affects greatly how efficiently it reflects light. This then impacts how well the diamond sparkles, its scintillation. The ideal angle for diamond pavilion facets is 41°. This is usually quite convenient, due to the octahedral shape of a standard diamond crystal. Unfortunately, diamond cutters can’t cut all mined diamonds to excellent proportions. Often, they must compromise between maximum brilliance and maximum yield (weight/carat retention). If cutters remove too much material from the diamond rough, they may cut away their profit. Thus, for economic reasons, many diamonds receive a cut with less than ideal proportions.
A little “cheating” finessing facets so they meet where they should, has no great impact on the stone. However, if a cutter varies a little further from the ideal cut angles, the diamond’s brilliance begins to suffer. If the cutter varies too far, you’ll get a diamond that just doesn’t compare to others in brilliance or fire.
Another factor to consider when you choose a diamond is its shape. An ideal-cut diamond should be symmetrical, not lopsided. (This point may seem obvious. Sometimes, however, it helps to point it out). A poorly proportioned gem can be “camouflaged” in its setting. Thus, you might not notice it until after you’ve bought it. Always examine a diamond loose, not in the setting.
The closer to colorless, the greater a white diamond’s value.
D, E, F –The highest grades for white diamonds. These colors are described as colorless.
G, H, I, J – These colors are described as “near colorless” or white.
K to Z – These colors are described as tinted, usually yellow or yellowish brown. Diamonds with colors K, L, or M are often said to “set white.” That means, if jewelers set them in yellow gold, the stones will appear white, since they have only slight tints. However, white gold or platinum settings would set off the tinted colors.
The further the grade goes down the alphabet, the stronger the tinting and lower the diamond’s value. However, once you get to the extreme end and the color becomes richer, you have a fancy colored diamond. No longer considered “off colored” white diamonds, their value starts going up again.
The size and number of inclusions inside a diamond determine its clarity. An inclusion can be another mineral, a fracture, or occasionally a void. Simply put, anything that will interfere with the free passage of light in a gem qualifies as an inclusion.
Diamond Clarity Grades
Just as with color, there are many possible clarity grades. Gemologists judge a diamond’s clarity based on what they can see at 10X magnification, under ideal conditions.
The highest grade a diamond can get is Flawless. That means you can see no inclusions at 10X magnification. However, this doesn’t mean you can’t find inclusions with higher magnification. Also, don’t assume it’s the only grade with no inclusions visible to the naked eye.
In addition to F for Flawless and IF for Internally Flawless, clarity grades use the letters V, S and I. They stand for Very, Small, and Inclusion. Numbers 1 to 3 further designate levels within grade.
After F and IF, clarity grades proceed as follows:
VVSI1 (Very, Very Small Inclusions One)
All these clarity grades indicate diamonds with no inclusions visible to the naked eye. These are all “eye clean.”
By far, carat or weight is the easiest quality factor to understand when you’re shopping for diamonds. Simply put, small diamonds are more common than large ones, but larger stones are more desired. Therefore, smaller diamonds cost less per carat than large ones. This explains why you’ll encounter jumps in price per carat as diamond sizes increase.
HOW TO CHOOSE A DIAMOND
Everyone’s diamond search is unique, but you may find this to be a helpful starting point.
First, identify the desired diamond shape.
Set a minimum carat weight.
Start with the highest quality diamond of the shape and carat weight minimum, and begin making concessions in the following order until you arrive at a diamond that fits your budget:
First, lower the Clarity: go as low as VS2 before making concessions in other areas.
The most popular range is the VS1-VS2 diamond. These diamonds appear flawless to the naked eye, and are a fraction of the price of a truly flawless diamond. Almost half of all diamonds purchased fall into this range. The next most popular range is SI1, where the inclusions are usually not significant enough to impact the appearance of the diamond for the casual observer. If you are primarily concerned with size and price, I1 may be your best clarity option. The larger the diamond, the easier imperfections are to detect; therefore Clarity becomes more important. For diamonds over 2 carats, a clarity grade of VS2 or higher is the safest bet for avoiding any signs of visible inclusions. In diamonds between 1 and 2 carats, clarity grades of SI1 or better will not have inclusions easily visible to the naked eye. In diamonds under 1 carat, clarity should be considered the least important of the traditional 4 Cs.
Next, lower the Color: Go as low as H before making concessions in other areas.
The vast majority of untrained observers (and many gemologists) cannot distinguish a color grade from the one just above or below unless the diamonds are compared side by side in a controlled environment. Even when side-by-side, changes in color are difficult to detect in I color and higher diamonds. Color becomes much harder to detect once a diamond is set in a ring and placed in an environment that contains color (as opposed to the all white background used in color grading). For instance, an H color diamond may look as colorless as a D when set in a ring under normal lighting conditions, especially if the two are not compared side by side. Colorless (D-F) fluorescent diamonds sell at a 5-15% discount to non-fluorescent diamonds since the fluorescence is perceived as a defect. In fact, the visible effects of faint to medium fluorescence are perceptible only to a gemologist using a special UV light source. Because the fluorescent glow is usually blue (which is the complementary color to yellow) fluorescence can make diamonds of I-M color appear up to one grade whiter. For this reason, I-M diamonds tend to sell at a slight premium when they possess Medium to Very Strong fluorescence. Overall, fluorescence should not be a major factor in the diamond purchase since its effects on appearance are negligible, if not slightly positive. The exception would be to exercise caution in purchasing a diamond with strong or very strong fluorescence in D-H color diamonds (which do not possess enough yellow color to offset the blue fluorescence).
Finally, lower the Cut: Go as low as Very Good in round diamonds, and Good in fancy shapes before making concessions in other areas.
Unlike the other “Cs” (Carat Weight, Color, and Clarity), the various Cut grades in existence today were not originated by GIA. Even though retailers use common terms to describe Cut (such as Excellent, Very Good, Fair, Poor) the terms are not uniformly defined or applied. In fact, a diamond seller may assign any cut grade they choose, based on any set of factors they wish. One retailer will use terms such as “Signature Ideal”, “Ideal”, and “Excellent”; while another uses “Ideal” to describe all three, and another uses “Excellent” for all. Be cautious when comparing cut grades from different retailers, as they are most likely inconsistent.
Also, be aware of diamond sellers who assign their own cut grades in place of what GIA has already assigned to a particular diamond. Many popular websites and retail stores display their own, more generous Cut rating in place of the GIA grade.
If the diamonds that match your revised criteria are close to your budget, consider shaving off some carat weight in order to close the gap. A carat weight difference of 10% or less will be very difficult to detect visually.
SHAPE BUYING TIPS
When selecting a diamond, your first priority is usually to choose a shape. If you’re unsure of what shape to choose, it may be helpful to know this: round diamonds are by far the most popular choice due to their incredible brilliance, fire, and light performance. Round brilliant diamonds make up about three-quarters of all diamond purchases, and offer maximum sparkle.
Princess diamonds feature an angular, contemporary beauty that looks gorgeous in classic and geometric settings, and are second in popularity, offering the brilliance of a round brilliant diamond at a lower price.
Cushion diamonds are an ideal choice for vintage-inspired settings, and radiant diamonds are a stunning alternative to princess and cushion diamonds for those preferring a rectangular shape.
Asscher and emerald diamonds are step-cut, for a sleek, elegant appearance. They emit less fire or sparkle than round diamonds but are more transparent.
Marquise, oval, and pear-shaped diamonds are more distinctive shapes, and help fingers look long and slender due to their elongated appearance. Marquise or pear-shaped diamonds may appear to be larger, given that more of the stone shows from the top view (looking down on the diamond).
Heart-shaped diamonds express your sentiment with a flourish and are often favored by die-hard romantics.
CERTIFICATION BUYING TIPS
All Labs are not created equal, and their judgments are not held to any objective standard. Unfortunately, some labs have succumbed to pressure from retailers to lower their standards, thereby allowing lower quality diamonds to be presented with higher ratings, increasing their value in the marketplace. Before relying on any certificate, make sure you are comfortable with the reputation and expertise of its author.
Use caution when comparing the price of diamonds graded by two different labs; what at first seems like a bargain may only be the result of more relaxed grading.
Only buy diamonds which have been certified by a reputable lab. Do not accept certifications created by retailers, even if they claim to be GIA trained.
Keep your certificate in a safe place. It provides invaluable security in the case of loss (helping to establish the quality and size of diamond required for equitable replacement), trade, or resale. Whenever the diamond must leave your possession (for example, to be cleaned), always let the party taking possession know you have a certificate. Knowing you can positively identify your diamond removes any temptation on the part of the third party to commit fraud (such as switching the diamond for one of lower quality).
A copy of your uniquely numbered GIA certificate is kept permanently on file with the GIA, and can be replaced at anytime if lost or destroyed.