The four Cs of quality

Rare precious stones such as diamonds have always fascinated. Whether diamonds serve as a symbol of love or are worn for other occasions, however you choose to invest in one you will definitely receive a unique companion forever.

A diamond’s value is determined using the four Cs: Carat, Clarity, Colour and Cut. These criteria influence the price to differing degrees. The carat, or weight, is the primary factor for determining the diamond’s price. The stone’s clarity comes next, followed by its colour and cut.

All of the stones offered by Les Ambassadeurs come with a worldwide recognised GIA certificate from the Gemological Institute of America. Our experts are happy to assist you in finding the exact diamond you are looking for.


The colour, clarity and size of a diamond are determined by nature. However, the right cut – which is when the stone is cleaved to it’s ideal proportions – allows the diamond to reveal its maximum brilliance or radiance. The round, classic brilliant cut with a minimum of 57 facets is considered ideal, but oval-, heart-, kiss- and drop-shaped diamonds are also popular.

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A practised eye can recognise the slightest nuances of colour in a diamond. The colours range from colourless to yellow and are graded with a scale from D to Z. D is the highest grade for colourless diamonds. A flawless white diamond is extremely rare, just as are coloured, or so called fancy diamonds. These have tones outside the D to Z colour grades and exist in many different colours such as red, pink, orange, yellow, green, blue, violet, brown, grey and black.

A further quality to consider is the diamond’s fluorescence. This can be seen using ultraviolet light and also affects, i.e. diminishes, the diamond’s value.

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The clarity, i.e. degree of purity, of a diamond is influenced by small imperfections, known as inclusions. These can usually only be seen under 10x magnification. Diamonds with black inclusions are generally rejected. When assessing inclusions, our experts ensure that they are never visible to the naked eye.

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The number of carats – an old measurement for weight – is the principal factor that determines a diamond’s price. 1.00 carat (ct) corresponds to 0.2 grams and is determined precisely using two decimal points. The heavier a diamond is, the more valuable it is. Following this logic, a two-carat diamond is normally of more value than two one-carat stones of the same quality (see description of “Clarity”).

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