Diamond Characteristics

The 4 main characteristics of a diamond are the cut, colour, clarity and carat weight, otherwise known as the “4 C’s”.

Cut

Cut refers to the angles and proportions a diamond cutter creates when transforming a rough diamond into a polished diamond. The cut is the most important characteristic in determining the brilliance of a diamond.

A well-cut diamond will reflect light internally from one mirror-like facet to another, dispersing it evenly out through the top of the stone. Diamonds that are cut too shallow and wide lose light through the bottom. If a diamond is cut too deep and narrow, light will escape out the side.

At DiamondExchange we carry only Ideal, Excellent, Very Good and Good cut grade diamonds, which produce the most brilliance.

Cut Grades
Ideal – All light is reflected through the top of the diamond. The highest level of brilliance. View our “Ice on Fire” Collection. 

Excellent – Nearly all light entering the diamond is reflected. Exceptional brilliance.

Very Good – Reflects most light entering the diamond. Very high brilliance.

Good – Not as brilliant as the Very Good cut but still a very bright diamond.

Fair – There is loss of light and it is noticeably less brilliant than the Good cut grade. DiamondExchange does not offer this cut grade.

Poor – Because the diamond has been cut too shallow or deep most light leaks out through the bottom or side of the diamond. DiamondExchange does not offer this cut grade.

Colour

Colour grading is determined according to how much colour or how little colour a diamond has. The colour is generally regarded as the second most significant characteristic of a diamond. This is because, after the diamond’s sparkle and brilliance, colour is the next feature most noticeable to the naked eye. The colour in a diamond ranges from completely colourless (D colour grade) to pale yellow (Z colour grade). The less colour a diamond has, the higher its colour grade and the greater its value. Colour grades D to J are regarded as colourless or near-colourless.

Diamond Exchange does not offer a colour grade lower than J (near-colourless).

Colour Grades

D Completely colourless. The highest colour grade. Extremely rare.

E-F Colourless. Only a trained gemmologist can detect colour. Very rare.

G-H Near-colourless. Colour is difficult to detect. Excellent value.

I-J Near-colourless. Colour is slightly detectable. Exceptional value.

K-M Noticeable colour. DiamondExchange does not offer these colour grades.

N-Z Strong noticeable colour. DiamondExchange does not offer these colour grades.

Clarity

Virtually all diamonds have natural imperfections known as inclusions or blemishes. The size, position and colour of these inclusions give a diamond its clarity grading. Generally most of these inclusions are not visible to the naked eye and have no discernible affect on the diamond’s brilliance. However, the fewer inclusions a diamond has the more rare the diamond and the greater its value. A diamond is said to be Flawless (FL) if no inclusions can be seen using magnification.

DiamondExchange offers only Flawless (FL), Very Very Slightly Included (VVS), Very Slightly Included (VS) and Slightly Included (SI).

Clarity Grades

FL, IF – Flawless, Internally Flawless. Flawless: no internal or external imperfections. Internally Flawless: no internal inclusions. Very rare.

VVS1-2 – Very Very Slightly Included. Very difficult to see inclusions using magnification. Exceptional quality./p>

VS1-2 – Very Slightly Included. Difficult to see inclusions using magnification. Less expensive than VVS clarity grading.

SI1-2 – Slightly included. Inclusions can be seen easily using magnification but usually not with the naked eye. Excellent value.

I1-3 – Included. Inclusions are visible to the naked eye. DiamondExchange does not offer this clarity grade.

Carat Weight

A “carat” is the standard measure of a diamond’s weight. As explained in our cut grade section the exact proportions have been calculated so that a diamond can be cut to reflect the maximum amount of light through the top of a stone. This means the weight of a well-cut diamond is proportionate to the millimetre width of the diamond. Therefore, although “carat” is a measurement of weight it is also an indication of size. 

If a diamond is cut too narrow and deep it will appear smaller than its weight would imply because some of the carat weight will be “hidden” in the base of the diamond. If a diamond is cut too wide and shallow it will have a large diameter for its given weight but will “leak” light through the bottom making it appear dull. A well-cut diamond will reflect the maximum amount off light back through the top of the stone making it appear larger.

DiamondExchange have created the following diamond chart showing how well-cut diamonds of different weights will appear when viewed from above (non-round shapes may differ depending on their length-to-width ratio).

Download our Diamond Size Chart