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Diamond Guide

Before you start diamond shopping, you need to have an in-depth understanding of what you’re buying. Our printed diamond guide (supplied by GIA) expands your knowledge on diamonds, so you can select your diamonds based on the same criteria that jewelers use to grade them.

You are invited to our “Diamond University”, where an expert member of our staff will COMPLETELY educate you about diamond knowledge (not merely “skim the surface” as others often do). We’ll spend 30-45 minutes, explaining every aspect of diamond knowledge and some areas to be careful of, when shopping for this most important purchase!

Diamond Education: The 4 C’s of Diamonds

This section describes the key characteristics of a diamond along with tips for its care. Understanding these characteristics will enable you to shop with confidence.

1. Cut

A diamond’s cut is the most important property to enhance its beauty because a well-cut diamond reflects light to maximize the stone’s brilliance. A diamond with perfect color and clarity could have poor brilliance if it is not well cut.

After proper cutting, the size of the stone may reduce by half, but its market value may increase more than four times for its brilliance and sparkle. Diamonds have a unique ability to manipulate light efficiently. This exceptional ability can be realized and maximized only by cutting and polishing the diamond with an extremely high level of accuracy.

It is very essential to know diamond anatomy before understanding cut.

Diamond anatomy

 
Diameter: Width of a diamond measured through the Girdle.
Table: Largest facet of a gemstone.
Crown: Top portion of a diamond extending from the Girdle to the Table.
Girdle: Intersection of the Crown and Pavilion which defines the perimeter of the diamond.
Pavilion: Bottom portion of a diamond, extending from the Girdle to the Culet.
Culet: Facet at the tip of a gemstone. The preferred Culet is not visible with an unaided eye (graded “none” or “small”).
Depth: Height of a gemstone measured from the Culet to the Table.

The cut of a diamond establishes how it reflects light, which is responsible for its sparkle or brilliance.

Cut has following three components:

 
1. Shape

A diamond cut by shape describes the outline of the stone and pattern of the facet arrangement. A stone can be cut in various shapes like Round, Princess, Heart, Oval, Pear etc. We will further explore various diamond shapes in the Shape section. The cut of a diamond establishes how it reflects light, which is responsible for its sparkle or brilliance.

2. Depth

A Diamond Cut by Depth is the ultimate feature for its brilliance and fire.

Shallow Cut: a shallow cut will lose light through a diamond’s bottom causing it to appear dull. Deep Cut: a deep cut will lose light through a diamond’s sides causing it to appear dark. Ideal Cut: An ideal cut is considered the best cut and it will reflect most or all of the light that enters the diamond back to the eyes. The quality of a diamond’s cut can be determined on the basis of its power to reflect light. The cuts can be broadly characterized as Ideal, Excellent, Very Good, Good, Fair or Poor. Ideal or excellent cuts release the inner brilliance of the stone and project maximum amount of fire and sparkle. Very Good, Good and Fair cuts lose some light that enters the diamond. A poor cut loses most of its light from the diamond sides / bottom and it may even have some “dead” spots inside.

3. Polish and Symmetry

Polish and symmetry are two important aspects of the cutting process. The diamond polish shows the smoothness of the diamond’s facets, whereas the symmetry refers to alignment of the facets. A poor diamond polish, or rough facets, can diminish a diamond’s brilliance, as well as its value.

2. Color

Diamonds are found in all colors of the rainbow, from colorless and transparent stones to ink black ones. Varying degrees of yellow or brown color is common in most of the diamonds and a slight difference in color can make a substantial difference in value. A truly colorless diamond is extremely rare and considered the most valuable. It allows the most light to pass through the stone and create the most brilliance.

During the formation of diamond from carbon, certain chemicals may have been drawn into the mix and result in added tinges of color in the transparent stone.

Most diamonds appear white to the naked eye, but they all include trace amounts of yellow or brown color. The color scale goes from D to Z (no diamond of color grade A, B or C has ever been found), with D being the most white and Z being the most yellow. The best way to see the true color of a diamond is by looking at it against a white surface.

 

Color Grade Table

Colorless

Stone looks absolutely clear and transparent, with no hint of color

Near Colorless

Stone looks clear and transparent. Color will be noticeable by experts only when compared to diamonds of better grades.

Faint Yellow

Color slightly detectable and will be noticeable by experts only.

Very Light Yellow

Stone shows an increasing yellow tint, even to an untrained eye.

Light Yellow

Stone appears yellow, even to an untrained eye.

Fancy

Bright, remarkable color – usually blue, pink, yellow, Red etc.

Fancy Colored Diamonds

Although majority of diamonds come in shades of white, there are also “Fancy” natural intensely colored diamonds available in colors like yellow, pink, greens, brown, red, orange, blue etc. These intensely colored diamonds are very rare, attractive and desirable. A deeply colored diamond can cost more than its colorless counterpart. These intensely colored diamonds are known as “Fancy” colored or “Fancies”. Fancy colored diamonds are graded in two ways. The first factor is the basic hue, such as pink, yellow, blue, green, etc. The second is the intensity. Both color characteristics form the basis for determining a fancy colored diamond’s worth. In fancy colored diamonds, a Z+ grade is used for their color grading. Usually, the more intense the color, the rare and expensive the diamond will be. For example, a fancy light pink diamond costs less than a fancy vivid pink diamond of equal size, shape and clarity. Though fancy colored diamonds rarely occur in nature, laboratories can easily create them through irradiation and heating. This process can permanently turn a natural colorless diamond into a fancy colored diamond. Treatments have also been developed to make lower-color white diamonds whiter. Irradiated colored diamonds have a significantly lower value than natural fancy diamonds and can be detected in a gem laboratory. 

Fluorescent Diamonds

Fluorescence is a form of illumination that is created when a diamond is exposed to low or high wave ultraviolet radiation. Fluorescence up to some extent is common in the majority of diamonds. Faint or medium fluorescence will rarely affect a diamond’s appearance. Usually fluorescence remains unnoticed by human eyes in ordinary light.

3. Clarity

Clarity is a term used to describe the absence or presence of flaws inside or on the surface of a diamond. In other words, the clarity of a diamond refers to a diamond’s clearness or purity.

When these flaws / marks occur internally, they are called inclusions. The most common types of inclusions include crystals, (tiny bubbles representing small minerals that were absorbed into the diamond while it was growing), internal graining, needles, knots, chips, cavities, cleavage, feathers, and clouds. On the contrary, when these flaws / marks occur on the surface, they are known as blemishes. The most common types of blemishes include polish lines, naturals, scratches, nicks, pits, transparent stress lines that appear on a diamond’s surface, surface graining, and extra facets. Blemishes are usually cut to remove a near-surface inclusion to raise the clarity grade of a stone. Most diamonds have these imperfections in them. Although many of these flaws are not visible to the naked eye, but under magnification, tiny featherlike shapes, crystals, bubbles and dark flecks become noticeable. These slight flaws make every diamond quite unique but they also affect the beauty and value of the diamond.

A diamond’s clarity is based on the number, size, nature, and location of imperfections on the finished stone. A diamond with higher clarity is more valuable in comparison to a diamond that contains numerous inclusions because it is less brilliant, as the inclusions interfere with light passing through it.

Clarity Grade Table

F

Flawless

Clear Stone, no inclusions or blemishes. Exceptional and beautiful diamonds.

IF

Internally Flawless

No inclusions and only insignificant surface blemishes. Rare and beautiful diamonds.

VVS1-VVS2

Very, Very Slightly Included – 1 & 2

Tiny inclusions, which are extremely difficult to find, even fewer than 10x magnifications. An excellent quality diamond.

VS1-VS2

Very Slightly
Included – 1 & 2

Minor inclusions, which are difficult to see under 10 x magnification. These stones are less expensive than the VVS1 or VVS2 grades.

SI1-SI2

Slightly Included –
1 & 2

Inclusions, which are easy to see under 10 x magnification. A good diamond value.

I1-I2-I3

Included –
1, 2 & 3

Inclusions, which are easy to see under 10 x magnification and sometimes, may be visible with the unaided eye. A good diamond value. Generally I3 grade is not used for jewelry purposes and mostly used in industrial applications.

4. Carat

The term “Carat” refers to the weight of a diamond. It is derived from the carob seeds, which are remarkably consistent in weight and shape and so were the favored scale balances in ancient times. This weight scale was standardized in 1907 and after that 1 carat became 0.2 grams or 1/142 of an ounce. Furthermore, each carat is divided into 100 points. Therefore, a ¼ carat diamond is 25 points and ½ carat diamond is 50 points and so on. This term ”Carat” is different from the term ”Karat” which is used to describe gold’s fineness or purity. When we consider all four Cs that determine the value of a diamond, we can find Carat weight most accurately and easily by using a delicately balanced scale capable of weighing extremely small stones.

 

There is one significant fact about diamonds’ weight and price. When diamonds are mined, large diamonds are discovered rarely in comparison of small ones, which make large diamonds much more valuable. For that reason, the price of a diamond rises exponentially with its size. So, a 2 carat diamond of a given quality is always worth much more than two 1 carat diamonds of equal quality. Although larger stones are often more highly valued, size should not be the only consideration. High brilliance, which varies according to clarity, cut, and color grade, is highly desirable in a diamond.