The Diamond Quality Pyramid is a framework to help you compare diamonds. While all diamonds are precious, those closest to the top of the pyramid -- possessing the best combination of cut, clarity, carat weight and color -- are the earth's rarest, most valuable and most beautiful to the eye. This diamond education page is a good introduction to understanding diamonds. If you have the basic understanding of the diamond qualities you will be able to make an educated purchase.
The Larger a Diamond, the Rarer it is. Larger diamonds are found relatively infrequently in nature, which places them at the most rare level of the Diamond Quality Pyramid. What also makes a bigger diamond so desirable is that it shows off a stone's fine color and cut, and therefore its brilliance, to its best advantage. Carat is actually a measurement of weight, NOT size. However, it should be relative to size. A diamond's size is measured in carat weight, and each carat is equal to 200 milligrams and is divided into 100 points. A .75 carat diamond is the same as a 75-point diamond or a 3/4 carat stone. While larger diamonds are highly prized, diamonds of equal size may vary widely in value and brilliance, depending on their qualities of clarity, cut, and color. Two diamonds of equal quality can have vastly different values depending on their cut, color and clarity. Carat weight is the easiest of the four C's to determine, however the diamond MUST be loose. Too many jewelers approximate carat weight, for instance, when you buy a 1/2 carat diamond, which you assume to be 50 points, you may actually be getting less than that. Many stores sell as low as 45 points, and represent it as "approximately" a 1/2 carat. There is nothing wrong with buying a "light" 1/2 carat, however the cost is significantly less. You should know that is what you are buying, and pay accordingly.
This is one of the most important of all characteristics, and among the hardest to judge. All other factors being equal, a poorly cut diamond can be worth less than half the value of a well “made” stone. The proportions of a stone as well as its polish and precision of faceting determine how much of the diamond’s potential fire and beauty may be released.
By cut, we are referring to two things, the first being the shape of the diamond. By this we mean round, marquise, pear, oval, princess, emerald, oval, heart or trillion. When a gemologist talks about cut, what is really being referred to is quality of proportions. The fact is many diamonds today are not cut as well as they could be. Many cutters choose to sacrifice some of the diamond's beauty to achieve a stone that is a larger carat weight. Cut, more than any other quality aspect, gives the diamond its sparkle. A diamond gets its brilliance and scintillation by cutting and polishing the diamond facets to allow the maximum amount of light that enters through its top to be reflected and dispersed back, also through its top. As you can see below, when all the angles are correct, the light that enters is dispersed back through the diamonds top facets. When a stone is cut too shallow or too deep, that light that enters through the top is allowed to escape through the bottom and does not allow the maximum beauty of the diamond to be realized. The reason these poorly cut diamonds are sold in stores is cost. The wholesale cost of these diamonds are significantly cheaper than a well proportioned diamond. Remember, just because two diamonds have the same weight, does not mean they are the same size.
Diamonds come naturally in almost every color of the rainbow, however most people are concerned with diamonds in the white range. Along with cut, this "C" is also very important in determining the overall beauty of the diamond. A diamond’s color is graded on an alphabetical scale from D-Z to describe how much or how little color a diamond possesses. With very few exceptions, diamonds that are graded as colorless are considered to be the most valuable. Truly colorless stones, graded D, are extremely rare and very valuable.
D-F: Colorless, perfect or almost perfect color.
G-J: Near colorless, good to very good color. This diamond may “face up” colorless when mounted.
K-M: Light but noticeable yellow or brown tint. May “face up” near colorless when mounted, especially when mounted in yellow gold. While many diamonds appear colorless, or white, they may actually have subtle yellow or brown tones that can be detected when comparing diamonds side by side. Diamonds were formed under intense heat and pressure, and traces of other elements may have been incorporated into their atomic structure accounting for the variances in color. A single change in color grade can significantly affect a diamond’s value. Although the presence of color makes a diamond less rare and valuable, some diamonds come out of the ground in vivid "fancy" colors--well-defined reds, blues, pinks, greens, and bright yellows. These are highly prized and extremely rare.
It is the lack of color, or whiteness in a diamond that allows the light to pass effortlessly through the stone and disperse that beauty back to the observer. Color is not white versus yellow, as the chart tends to indicate, it is lighter versus darker. A white diamond will look very clean, crisp, and brilliant, with a lot of pizzazz. A yellow diamond will not really look yellow, as it will look darker and dirty, without nearly the same brilliance. These are differences that you can clearly see, as you do not need to be a gemologist to see these differences.
The Purer a Diamond, the More Brilliant The greater a diamond's clarity, the more brilliant, valuable and rare it is -- and the higher it is on the Diamond Quality Pyramid.
Clarity refers to how many flaws, or inclusions, are in the diamond. In most cases, clarity has very little to do with the beauty of the diamonds, rather it effects how the diamond looks under the microscope. To determine a diamonds clarity grade, it must be examined loose, under 10x magnification by a gemologist. Whatever minute inclusions there may be makes every diamond unique. These are nature's birthmarks, and they may look like tiny crystals, clouds, or feathers, and in most cases do not mar the diamond's beauty nor endanger in durability. Without high magnification, these flaws are invisible. However, the fewer inclusions, the more rare your diamond will be. Diamonds categorized as internally flawless reveal no such inclusions. Flawless stones are at the peak of the Diamond Quality Pyramid and are treasured for their rarity and beauty. Diamonds with very, very small inclusions are graded as VVS1 or VVS2. The larger the inclusion, the lower the grade and the less rare the diamond. Inclusions that can be seen with the naked eye are graded I1 or I3.
The number, color, type, size and position of surface and internal birthmarks affect a diamond's value. Major inclusions can interfere with the path of light that travels through a diamond, diminishing its brilliance and sparkle and therefore its value.
The fewer and smaller the inclusions, the more rare and valuable the diamond. Less than 1% of all diamonds ever found has had no inclusions and can be called internally flawless (IF).
The following are abbreviations for terms that are used world wide to describe the clarity of a diamond:
IF,VVS1,VVS2: Internally flawless or near flawless. Impossible to extremely difficult to find any inclusions, even under 10x magnification. IF is Internally Flawless, and VVS1 and VVS2 are “Very, very slightly included”.
VS1,VS2: 100% clean to the naked eye, and moderately difficult to very difficult to find inclusions with 10x magnification. VS1 and VS2 are “Very slightly included”.
SI1, SI2, SI3: Should be completely to almost completely clear to the naked eye (eye clean) when viewed from the top. Fairly easy to find imperfections with 10x magnification. SI diamonds are “Slightly included”.
I1, I2, I3: Borderline “eye clean” too fairly easy to find imperfections with the naked eye.