Yes, all diamonds are sparkly, and it can be easy in your excitement to get drawn in by a salesperson and just purchase the first one you are shown, especially if it is in a pretty setting. In reality, it is important to actually know what you are purchasing. Like with most large purchases, it is valuable when looking to buy a diamond to comparison shop. One diamond can look great by itself, but when held up to another, better diamond it can appear dull, lifeless, and yellow in comparison. In order to understand what to look for and how to ask about a diamond’s quality, you should know that diamonds are graded according to four main criteria: Cut, Clarity, Color, and Carat. These are known as the 4 C’s.
How to Choose a Diamond
Unlike shape, which refers to the overall shape of the diamond, round, oval, marquise, etc., a diamond’s cut refers to the quality of its cut or faceting, which I will be describing here.
The brilliance of a diamond depends heavily on its cut. A well-cut diamond will appear very brilliant and fiery, while a poorly cut stone can appear dull and lifeless, regardless of its color or clarity. Some consider cut the most important of the four C’s because it has the greatest influence on a diamond’s appearance. When a diamond is cut with the proper proportions, light is reflected out of the top of the diamond (known as the table). If it is cut too shallow, light leaks out of the bottom. If it is it cut too deep the light will escape out of the side.
If you are buying a diamond in person the best way to determine the quality of the cut is to see how it sparkles in comparison to other diamonds. Tip: many jewelry stores employ fancy, expensive lighting to make their diamonds appear more brilliant than they actually are. To make sure you are really getting a well cut stone, that will still appear brilliant when you take it outside, hold your hand over the diamond and hide it from the lights. It should still sparkle.
If you are buying a stone or ring online, as is increasingly becoming popular, the quality of the cut can be more difficult to discern. The online retailer James Allen solves this by offering high-definition, rotating views of their loose stones on their website. This always you to see how the diamond really sparkles before purchasing it. For this reason, I recommend James Allen over Blue Nile as Blue Nile does not offer videos, or even pictures of their diamonds listed for sale.
Like most things in life, diamonds are not perfect. Almost all diamonds contain some inner flaws, or inclusions, that occur during the formation process. These can look like small feathers, crystals, or clouds. Black carbon spots are also common. The visibility, number and size of these inclusions determine what is called the clarity of a diamond. Diamonds that are clear create more brilliance, and thus are more highly prized. They are also more rare, especially for larger stones, and are priced accordingly. Many inclusions are very small and can only be seen through a 10x power magnifying loupe. However some can be easily discernible to the naked eye. Diamonds clarity is graded on an internationally recognized scale developed by the Gemological Institute of America(GIA) from flawless (FL) to obvious inclusions (I3).
“The GIA Clarity Scale contains 11 grades, with most diamonds falling into the VS (very slightly included) or SI (slightly included) categories. In determining a clarity grade, the GIA system considers the size, nature, position, color or relief, and quantity of clarity characteristics visible under 10× magnification.”
On a diamond grading report all of a stone’s inclusions will be mapped out as in the examples below.
Flawless (FL) – No inclusions or blemishes are visible to a skilled grader using 10× magnification
Internally Flawless (IF) – No inclusions and only blemishes are visible to a skilled grader using 10× magnification
Very, Very Slightly Included (VVS1 and VVS2) – Inclusions are difficult for a skilled grader to see under 10× magnification
Very Slightly Included (VS1 and VS2) – Inclusions are minor and range from difficult to somewhat easy for a skilled grader to see under 10x magnification
Slightly Included (SI1 and SI2) – Inclusions are noticeable to a skilled grader under 10x magnification
Included (I1, I2, and I3) – Inclusions are obvious under 10× magnification and may affect transparency and brilliance”
(From the GIA website)
I would advise against buying a diamond graded in the I1, I2, I3, range as I feel the amount of inclusions in these grade stone are distracting, and definitely detract from the beauty of the diamond. Furthermore, they tend to cloud and dull the stone.
VS1 and VS2 tend to offer the best balance of quality and value. With VS1 and VS2 stones you want to look for diamonds that are considered “eye clean”. That is, their inclusions are only visible when viewing under magnification. To the naked eye, their inclusions appear invisible.
Color usually refers to the presence or absence of color in white diamonds. When dealing with non-fancy colored diamonds, white, or colorless stones are the most desirable because they allow the most refraction of light and will thus sparkle more. Off-white diamonds absorb light, making them less brilliant. Diamonds are graded for color on a letter scale from D-Z, with D being the highest grade and colorless and Z being the lowest grade. It is advisable not to buy a diamond graded lower than a J, and most large online stores like Blue Nile do not even carry any diamonds graded lower. These stones will usually appear yellowish, or brownish, with a deeper tint the closer they get to Z.
Although they are graded all they way to Z, pick a diamond in the colorless or near colorless category; D-J.
Near colorless diamonds (in the G-J range) offer a great value for their price. Any color apparent in diamonds in this range will usually become undetectable to an untrained eye once the diamond has been mounted in a ring. Furthermore, if you are planning to have a diamond set in a yellow gold ring, there is little point in spending considerably more on a colorless diamond, as the yellow of the gold will be reflected somewhat through the diamond, canceling out the diamond’s colorless effect. White gold and platinum tend to have the opposite effect, instead enhancing a diamond’s whiteness.
Carat refers to the weight of the diamond. Diamonds are sold by the weight, and the other three C’s (cut, color, and clarity) all affect how much each diamond is worth per carat. A flawless, round one-carat perfectly white diamond can sell for $25,000, whereas a one-carat slightly included (SI2) marquise-cut diamond, with J color (the lowest grade in near colorless) can sell for less than $3,000. There are 100 points to a carat. So if you hear someone talking about a 60 point diamond, they mean that it is 0.60 of a carat. The larger the diamond, the more rare it is, so all other factors being equal, a single 1.0 carat diamond will cost more than 4 quarter carat diamonds. The price of diamonds goes up exponentially with size.
Diamonds below are not to scale. Diagram is meant to show relative differences in size for different carat weights. Keep in mind that diamonds of the same carat weight can appear to be slightly different in size depending on the quality of the cut. One way of determining the quality of a diamond’s cut is how close it comes to the ideal standard diameter for that size. For example, a one-carat ideal-cut round brilliant diamond should be approx. 6.5 mm in diameter.