The Diamond Guide
If you are thinking about owning a diamond, be it a solitaire or a piece of jewelry set with diamonds, you are entering an enchanted world of romance, intrigue, legend and history that was once reserved for kings and emperors. Until a century ago, only the wealthy could afford the luxury of lavishing themselves with diamonds. Fortunately, since the discovery of large deposits in Africa and throughout the world, diamonds are now available in a variety of sizes, shapes, colors, and affordable price ranges.
The Four C’s of Diamonds
The The Four C’s are the key characteristics of diamonds: Clarity, Color, Cut, and Carat weight. Taking a few minutes now to learn about them will make your purchasing experience smarter, easier and more enjoyable. Not only will you know the exact quality of the diamond you’re considering, but you’ll be confident that you’re paying a fair market price for it. The Four C’s give you the information you need to compare the characteristics of diamonds within one jewelry store or from one store to the next.
Because diamonds are so valuable, it’s essential to have a universal grading system for comparing their quality. In the 1940s and ’50s, GIA developed the Four C’s and the GIA International Diamond Grading System™ to objectively compare and evaluate diamonds. This system essentially involves the Four C’s and provides standardization for the certification of diamonds.
Carat
Diamonds and other gemstones are weighed in metric carats: one carat is equal to 0.2 grams, about the same weight as a paperclip. (Don’t confuse carat with karat, as in “18K gold,” which refers to gold purity.)
Just as a dollar is divided into 100 pennies, a carat is divided into 100 points. For example, a 50-point diamond weighs 0.50 carats. But two diamonds of equal weight can have very different values depending on the other members of the Four C’s: clarity, color and cut. The majority of diamonds used in fine jewelry weigh one carat or less.
Because even a fraction of a carat can make a considerable difference in cost, precision is crucial. In the diamond industry, weight is often measured to the hundred thousandths of a carat, and rounded to a hundredth of a carat. Diamond weights greater than one carat are expressed in carats and decimals. (For instance, a 1.08 ct. stone would be described as “one point oh eight carats,” or “one oh eight”.) If the ct Diamond was $5000.00 per carat the 1.08ct would be $5400.00.
Clarity
Because diamonds formed deep within the earth, under extreme heat and pressure, they often contain unique birthmarks, either internal (inclusions) or external (blemishes).
Diamond clarity refers to the absence of these inclusions and blemishes. Diamonds without these birthmarks are rare, and rarity affects a diamond’s value. Using the GIA International Diamond Grading System™, diamonds are assigned a clarity grade that ranges from flawless (FL) to diamonds with obvious inclusions (I3).
Every diamond is unique. None is absolutely perfect under 10x magnification (using a jewelers loupe), though some come close. Known as Flawless diamonds, these are exceptionally rare. Most jewelers have never even seen one.
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 10x magnification.
- Flawless (FL) – No inclusions or blemishes are visible to a skilled grader using 10x magnification
- Internally Flawless (IF) – No inclusions and only blemishes are visible to a skilled grader using 10x magnification
- Very, Very Slightly Included (VVS1 and VVS2) – Inclusions are difficult for a skilled grader to see under 10x magnification
- Very Slightly Included (VS1 and VS2) – Inclusions are clearly visible under 10x magnification but can be characterized as minor
- Slightly Included (SI1 and SI2) – Inclusions are noticeable to a skilled grader using 10x magnification
- Included (I1, I2, and I3) – Inclusions are obvious under 10x magnification and may affect transparency and brilliance
Color
The diamond color scale:
- Colorless: D, E, F
- Near colorless: G, H, I, J
- Faint yellow or brown: K, L, M
- Very light yellow or brown: N, O, P, Q, R
- Light yellow: S, T, U, V, W, X, Y, Z
Diamond color is all about what you can’t see
Diamonds are valued by how closely they approach colorlessness – the less color, the higher their value. (The exception to this is fancy-color diamonds, such as pinks and blues, which lie outside this color range.)
Most diamonds found in jewelry stores run from colorless to near-colorless, with slight hints of yellow or brown.
GIA’s color-grading scale for diamonds is the industry standard. The scale begins with the letter D, representing colorless, and continues with increasing presence of color to the letter Z, or near-colorless. Each letter grade has a clearly defined range of color appearance. Diamonds are color-graded by comparing them to stones of known color under controlled lighting and precise viewing conditions.
Many of these color distinctions are so subtle as to be invisible to the untrained eye. But these slight differences make a very big difference in diamond quality and price.
Cut
Cut is the factor that fuels a diamond’s fire, sparkle and brilliance. The image to the right shows how important the proper cut can be in making the diamond as brilliant as possible. If the diamond is cut too deep or too shallow, it will not reflect light back to the eye in the most optimal fashion possible and the diamond won’t have that fiery brilliance that is so sought after.
The traditional 58 facets in a round brilliant diamond, each precisely cut and defined, are as small as two millimeters in diameter. But without this precision, a diamond wouldn’t be nearly as beautiful. The allure of a particular diamond depends more on cut than anything else.
Though extremely difficult to analyze or quantify, the cut of any diamond has three attributes: brilliance (the total light reflected from a diamond), fire (the dispersion of light into the colors of the spectrum), and scintillation (the flashes of light, or sparkle, when a diamond is moved).
An understanding of diamond cut begins with the shape of a diamond. The standard round brilliant is the shape used in most diamond jewelry. All others are known as fancy shapes. Traditional fancy shapes include the marquise, pear, oval and emerald cuts. Hearts, cushions, triangles and a variety of others are also gaining popularity in diamond jewelry.
As a value factor, though, cut refers to a diamond’s proportions, symmetry and polish. For example, look at a side view of the standard round brilliant. The major components, from top to bottom, are the crown, girdle and pavilion. A round brilliant cut diamond has 57 or 58 facets, the 58th being a tiny flat facet at the bottom of the pavilion that’s known as the culet. The large, flat facet on the top is the table. The proportions of a diamond refer to the relationships between table size, crown angle and pavilion depth. A wide range of proportion combinations are possible, and these ultimately affect the stone’s interaction with light.
In early 2005, GIA unveiled a diamond cut grading system for standard round brilliants in the D-to-Z color range. This system, the product of more than 15 years of intensive research and testing, assigns an overall diamond cut grade ranging from Excellent to Poor.
Standard Stone Shapes
As the old saying goes, beauty truly is in the eye of the beholder. Therefore, which diamond shape you should choose is a matter of personal preference and why Zadok Jewelers carries many different shapes and sizes of stones. Each have their attraction and benefits and below we try to provide you with some information about each to help you better decide which shape is best for you.
The most popular non-round diamond, its beautiful brilliance and unique cut make it a favorite for engagement rings. The princess has pointed corners and is traditionally square in shape. Princess-cut diamonds can vary greatly in how square or rectangular they are. To find the dimension of princess you want, ask your salesperson about the length-to-width ratio. This will determine what the diamond will look like when viewing it from above. Here are length-to-width ratios for princess-cut diamond shapes that are pleasing to the eye. For a princess diamond shape that is square, look for length-to-width ratios between 1 and 1.05. If you prefer more of a rectangular shape, look for length-to-width ratios greater than 1.10.
Oval Cut Diamond
An oval cut diamond has beautiful brilliance that’s similar to a round diamond. To find the dimension of oval you want, look for the length-to-width ratio in our interactive diamond search and on each diamond’s detail page. The length-to-width ratio will determine the diamond’s outline, or what it will look like when viewed from the top. For the most traditional oval diamonds, look for length-to-width ratios between 1.33 and 1.66.
Marquise Cut Diamond
The shape of a marquise diamond can maximize carat weight, giving you a much larger-looking diamond. To find the dimension of marquise you want, as a salesperson about the length-to-width ratio. The length-to-width ratio will determine the diamond’s outline, or what it will look like when viewed from the top. For the most traditional marquise-cut diamonds, look for length-to-width ratios between 1.75 and 2.25.
Heart Cut Diamond
The heart is the ultimate symbol of love. The unique look of the heart-shaped diamond helps make it a distinctive choice for a variety of diamond jewelry. When choosing a color grade, consider that while the price of a J-color heart shaped diamond is exceptional, color may be slightly visible in its corners. To find the dimension of heart-shape you want, look for the length-to-width ratio in our interactive diamond search and on each diamond’s detail page. The length-to-width ratio will determine the diamond’s outline, or what it will look like when viewed from the top. For a more traditional heart-shaped diamond, look for length-to-width ratios between .90 and 1.10.
Emerald Cut Diamond
What makes this shape different is its pavilion, which is cut with rectangular facets to create a unique optical appearance. Due to its larger, open table, this shape highlights the clarity of a diamond. If you choose an emerald-cut with a lower clarity grade, such as SI, be sure to review the clarity plot on the diamond certificate. Also, emerald-cut diamonds can vary greatly in how rectangular they are. If you’d prefer an emerald cut with a squared outline, look for an Asscher-cut diamond. To find the shape of emerald you want, look for the length-to-width ratio in our interactive diamond search and on each diamond’s detail page. The length-to-width ratio will determine the diamond’s outline, or what it will look like when viewed from the top. For the classic emerald-cut shape, look for a length-to-width ratio between 1.30 and 1.40.
Cushion Cut Diamond
This shape has been around for hundreds of years and due to the shape of these diamonds, they are also known as “pillow cut” diamonds. The corners of these diamonds are rounded and the facets are cut larger to increase the shine of the diamonds. The large facets give rise to clarity in the appearance of the diamonds. You can buy these diamonds in square and rectangular shapes. Cushion cut diamonds are rising in popularity by the day. If you take a closer look at these diamonds, they look like a combination of a Radiant and Round brilliant.
Radiant Cut Diamond
The name says it all. The Radiant cut combines the shape of an emerald cut gem with the sparkle of a brilliant cut rectangular gemstone.
Radiant diamonds were introduced to the diamond world in the 1970’s and received their name due to the tremendous amount of brilliant white light and colorful fire that “radiate” from the stone. This radiance is the result of the shape’s high number of facets, totaling 70, which allow white light to be broken into all of the spectral colors and reflected throughout the stone many more times than a shape with less facets. When looking directly down through the table* (large flat facet on top of a diamond) of a well cut radiant diamond, one would see the illusion of infinite sparkle and reflection, often similar to the mirror effect in a “House of Mirrors.” Although the Radiant cut has the same look or outline of an Emerald cut, the difference lays in the amount of facets required for each shape. The Emerald cut has Far fewer facets than most other shapes, which gives it a calmer, pristine look similar to a tranquil pool of water. On the other hand, the Radiant cut diamond, with over 70 facets, lights up with brilliance and color like fireworks on New Year’s Eve.
Radiant diamonds are unique and what make them so are the corners that are trimmed with utmost care and perfection. The cut is also one of the reasons why this diamond is used with a number of other diamond cuts and used in making some exquisite jewelry pieces. Even when this diamond shape is set with round or baguette diamonds, it will make a striking appearance and give a new look to the jewelry item. The rectangularity in these diamonds can vary largely. When looking for Radiant cut diamonds, make sure that you take a look at the length width ratio, as they can be cut into perfectly symmetrical squares as well as elongated rectangular shapes.
