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The 4C's

These characteristics do not only determine the stone’s quality, they can also be very useful in identifying the diamond, since every diamond is unique.

The quality of a diamond is defined by means of the C’s: Carat, Clarity, Colour and Cut.


Carat refers to the weight of a diamond.

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The clarity or purity of a diamond is determined by the number, size, brightness and location of the internal and external characteristics, important structure phenomena and transparency.

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Over 90% of all gem diamonds have a basically yellowish colour. The intensity can vary from nearly colourless, which is preferable, to decidedly yellow.

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The proportions and finish grade of a diamond establish the quality of the cut.

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