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Diamond Buying Guide

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Story of Diamonds

Diamonds have a history that stretches almost as far back as the earth itself. Formed deep underground over millions of years and through immense heat and pressure, diamonds were forced towards the earth's surface by volcanic activity. Made up of only carbon, the diamond is the purest of all precious stones. Its unparalleled strength makes it last forever, perhaps why it has been adopted as the symbol of love.

These gemstones have been surrounded by myth and legend for centuries. In Greek times it was believed that diamonds were remnants of fallen stars. Diamonds have also been connected with romance for thousands of years. The ancient Egyptians believed that you should wear your diamond on the third finger of your left hand, which contains the 'vena amoris' (vein of love), which flows directly to the heart.

Diamond Standards

Buying a diamond should be based on the right knowledge, as they come in many qualities. The four C's - CLARITY, CUT, CARAT and COLOUR - are used worldwide to describe the quality of diamonds. This booklet defines these four important points in more detail.

The rarest and most valuable diamonds are the clearest and purest of colour. Other factors that determine a diamond's quality and value are its symmetry and cut proportions. Learning as much as possible about the differences in quality and value will help you choose the right diamond. If you have any queries, feel free to ask one of our trained staff.

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A diamond has the capability to refract more light than any other gemstone. One which is free of interior inclusion or exterior flaws has nothing to interfere with the passage of light through the stone and so is considered to be of the highest quality. Such stones are very rare and are correspondingly, of a higher value.

Most diamonds contain tiny natural marks called inclusions. The number of inclusions, their size and location all affect the diamond's clarity grade. While it is true that a clearer a diamond, the better, minor inclusions will not compromise a stone's beauty or endanger its durability.


It is the cut that allows a diamond to make the best use of light. When a diamond is cut to the right proportions, light is refracted internally from one facet to another before being dispersed through the top of the stone.

If the cut is too deep, some light will escape through the opposite side of the pavilion; too shallow and light will escape through the pavilion before it can be refracted. A master cutter ensure full light dispersion, maximising the inherent beauty of the stone.

An ideal cut diamond makes full use of the light entering it, maximising it's brilliance and 'fire'.

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The size of a diamond is measured in carar-weight. One carat is divided into 100 'points', so that a diamond of 75 points, weighs 0.75 of a carat.

While carat-weight is the most obvious factor when assessing the value of a diamond, two diamonds of equal size can have very different values, depending on their respective cut, clarity or colour. Bigger is not necessarily better - diamonds of high quality can be found in all size ranges. However, one diamond of one carat is normally worth more than two diamonds of 0.50ct. each.


The best colour for a diamond is no colour at all. These are know as 'white diamonds'. Other rare diamonds with a pure colour, such as pinks, blues or greens, are also valuable and are known as 'Fancies'.

Colour grading scales from colourless to light yellow. The differences from one grade to another are very subtle, evidenced by the number of grades within each category shown on the International Colour Grading Systems Chart (see below).

Diamonds range from colourless - the rarest and most valuable - to yellowish, with a series of shades in between.

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