Diamonds 101

Exquisite beauty can come in very small packages. Diamonds are one of nature’s most beautiful and most valuable gems. Valued for its brilliance and its association with never ending love…

The 4 Cs


Of all the four Cs, cut has the greatest effect on a diamond’s beauty. The cutter’s skill in fashioning the diamond from rough is of great importance.

Diamonds manipulate light very efficiently. Cutting and polishing the diamond to a high level of geometric accuracy enhances diamond’s ability to play with light and reflect it back to the individual eye. GIA (Gemological Institute of America) and AGS (American Gem Society) consider the proportions of a diamond cut and also the craftsmanship of its overall symmetry and polish.

There are many shapes into which diamonds are cut. Traditional fancy cuts are the marquis, pear, oval, princess, heart and emerald cuts. Of all the cuts, the brilliant cut has 58 facets and is designed to create the most brilliance and scintillation (play of light) within the diamond and is considered the most desirable.

Diamonds today are also sold in their raw crystal forms, often as drilled beads. These crystals are natural shapes and colors and can be very beautiful.


Truly colorless diamonds are extremely rare. Almost all diamonds have varying degrees of body color. Very slight differences in gem body color can make a difference in the value of the gem. The quality of the cut can disguise some coloration. Extreme body colors in diamond are also rare and very valuable. These are considered “fancy” colored diamonds.

GIA/AGS are the standard grading systems for diamonds. The scale starts with D color and ranges down to K color. D color diamonds are considered colorless and most valuable. K color diamonds are yellow/brown, not fancy.

Grading for color requires a skilled and practiced diamond appraiser who will utilize special lighting and a master diamond color comparison set to determine an individual diamond’s color properties.


Clarity involves the determination of the diamond’s internal characteristics. Every diamond has a completely unique “fingerprint” which is identified by finding and mapping the gems internal inclusions. The fewer inclusions; the more desirable the diamond and the more valuable. Sometimes diamonds will form around other crystals. These are simply minerals that were trapped inside the diamond. Feathers are breaks in the diamond. Blemishes are only on the surface of the diamond.

Jewelers use a magnification of 10 to see into the diamond and to evaluate the size, location, nature, number and color of all inclusions and blemishes of a gem. Using the GIA/AGS grading system a clarity grade from flawless to I (included) is assigned.


Carat is a measure of weight. One carat equals 1/5 of a gram. Each carat is further divided into points. A point equals 1/100th of a carat. The weight of a diamond is the easiest measure of the four Cs to determine accurately. While larger diamonds tend to cost more, bigger is not always better. If the diamond is poorly cut, heavily included, tending toward yellow in color, added weight may only reduce the diamonds brilliance and value.

Tip: Don’t confuse carat with karat. Karat is a measure of gold purity.

Images and scales are from GIA.

The Brilliant Cut


This refers to the flat top of a cut stone. It is sometimes called as its face.


This refers to the portion of a cut stone above the Girdle. It consists of a large flat area on top called a table, and several facets below it. These include the Star Facet, Bezel Facet and Upper Girdle Facet respectively.


This refers to the edge formed where the top (crown) and bottom (pavilion) of a stone meet. The girdle is the area normally grasped by prongs when a stone is mounted onto a setting. Many diamonds are also finished with a fully polished or even a faceted girdle. The girdle is rated in terms of its thickness.


The pavilion is the bottom portion of a cut stone, beginning at the girdle and going to the point at its end. It includes two separate facets namely the Lower Girdle Facet and the Pavilion Facet.


The culet refers to the bottom point of the diamond. In many cases this point actually has a very small facet. The culet is referred to in terms that relate to the presence or size of this facet.

How to Buy a Diamond

Learn as much as you can about diamonds. Today you can search the web for lots of answers to your questions and it is a good source of information. Nothing can take the place of talking to your trusted jeweler and actually looking and comparing real diamonds in person. Feel free to ask a lot of questions. Decide which Diamond properties are the most important to you. Consider writing the 5 Cs down (Cost, Carat, Color, Clarity, & Cut) in their order of importance. At Christopher’s we work with many trusted suppliers of diamonds and we can show you at least two diamonds with similar properties. This allows you to compare directly. It is likely you will prefer them diamond with the best cut and finish and the best color.


As you compare prices on diamonds from many different sources, remember that you can only compare prices of diamonds with similar characteristics and properties. Even a slight change in the grading of the properties of a diamond can greatly affect the price. Price is also affected if the diamond is certified by a reputable lab or non-certified.

Color and Clarity

In general these two properties tend to be most important to most people. A premium is often paid for very high color graded diamonds (D & E) with an ideal brilliant cut. It would make no sense to accept a low clarity grade in such a diamond. Try matching these two properties based on your preferences and budget. You can often save a bit by keeping the clarity grade high and giving a bit on color.

Visit your trusted jeweler and work face-to-face to learn about, see, and purchase your diamond.