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Diamond Characteristics
The value of a diamond is determined by four factors known as the „Four C‟s‟; Cut, Colour, Clarity and Carat.
All four factors should be considered when choosing a diamond but it is worth remembering that a good
quality small stone is generally worth more than a poor quality larger stone.
The cut refers to a diamonds proportions, symmetry and polish. The round brilliant cut has 57 or 58 facets that
reflect the maximum amount of light. A well-cut diamond will reflect the light and return it back out to your
eye; if the diamond is cut too shallow or too deep, light will be lost through the back of the stone. The
proportions of a diamond refer to the relationships between table size, crown angle, and pavilion depth. A
wide range of proportion combinations are possible, and these ultimately affect the stone‟s synchronicity with
light. The cut of a diamond has three attributes: brightness (the total light reflected from a diamond), fire (the
dispersion of light into the colours of the spectrum), and scintillation (the sparkle when a diamond moves). Cut
should not be confused with shape.
Few „white‟ diamonds are completely colourless. Most have a tinge of yellow or brown, caused by the presence
of nitrogen impurities. The closer to colourless the diamond is, the more valuable it becomes. The most
popular and well known scale for grading the colour of diamonds is the alphabetical scale developed by the
Gemological Institute of America (GIA). The scale ranges from D to Z, where D is colourless and Z is tinted
A small percentage of diamonds are found in intense pure colours from yellow to black, through pink, blue,
green and the rarest of all, red. The colour may be enhanced by heat treatment or irradiation; artificially
coloured diamonds are less valuable than natural colour diamonds. These coloured diamonds are known as
„fancies‟ and are graded separately according to the intensity of the hue, tone and saturation of the colour.