The 4C's of diamond grading |
| Diamonds are graded internationally to a set of standards commonly known as the 4C's. The 4C's consist of Carat Weight, Colour, Clarity and Cut. Typically, an untrained eye sees only carat weight and cut |
| Carat Weight |
| Carat, abbreviated 'ct', is a measure of weight, not size. One carat is equal to one fifth of a gram, and is based on the weight of a carob bean from ancient Egypt. |
| A diamond's weight is measured in carats, abbreviated ct. One carat can be divided into 100 points. Therefore, a diamond weighing one quarter of a carat can also be referred to as being 25 points. |
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| Colour |
| Many people consider diamonds to be colourless. In fact, diamonds come in every colour of the rainbow, as well as black. Moreover there are varying degrees of intensity of each colour. |
| A diamond's colour is determined on a colour scale from D (colourless) to Z (yellow/brown). The most sought after diamonds have no colour. Whilst most diamonds appear to have no colour, in actual fact they have tints of colour as shown on the colour scale. |
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| Clarity |
| Virtually all diamonds possess natural imperfections. These natural phenomena, called inclusions, can usually only be seen under the power of 10x magnification. They may look like tiny crystals, clouds, or feathers |
| Refers to the amount and size of natural imperfections in the diamond. This may be internal (inclusions) or external (blemishes). The fewer inclusions in a diamond, the rarer and more valuable the gem. |
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| Cut |
| While nature determines a diamond's clarity and colour, cut is determined by the artistry and skill of the craftsman. Cut more than any other characteristic, gives the diamond its sparkle |
| This does not refer to the overall shape of the diamond but rather the quality of the cutting. It is the single most important aspect of any diamond. The proportion, finish and symmetry of the external facets of the diamond are what creates the fire and brilliance. A diamond may be colourless and flawless but if it is not cut well it will appear dull and lifeless. |
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