4CS OF DIAMONDS
CUT
Fire, brilliance and scintillation.
COLOUR
More rare and valuable it is
CLARITY
Natural inclusions or imperfections
CARAT
Weight Valuations
CHOOSING THE RIGHT DIAMOND
Diamonds are graded using a universal system that assesses the stone on its colour, clarity, cut and carat-weight, commonly known as the ‘Four Cs’. Every diamond, no matter how large or small, has a set of unique characteristics that determine its value.
CUT
A diamond’s cut is not just a description of its shape, it is the most important factor in determining its fire, brilliance and scintillation. While nature determines the colour, clarity and carat of a stone, the cut is in the hands of the master diamond cutter.
Essentially, the cut of a diamond determines how effectively light that enters the stone is refracted within and reflected back through the top of the diamond. Factors such as proportion, symmetry and polish affect the quality of the diamond: the closer they are to perfect, the better the diamond will perform in terms of fire, brilliance and scintillation.
A diamond cut to ideal proportion and symmetry will reflect the perfect balance of light back through the top of the stone, while a poorly cut diamond will result in a loss of light, and hence sparkle, through the sides and bottom.
CUT
COLOUR
​Colour refers to the presence or absence of a yellow or brown tint in white diamonds. The closer a diamond is to colourless, the more rare and valuable it is. Most diamonds appear colorless to an untrained eye, yet many have slight tones of yellow or brown which affect its value. (The exception to this is fancy-coloured diamonds, such as deep yellows, pinks and blues, which lie outside the white diamond colour range.) The colour of a diamond is measured on an alphabetical scale starting from D (colourless). Each letter grade has a clearly defined range of colour appearance that determines its value, and as you move down the scale, the colour tint in the diamond increases.
FLUORESCENCE
Fluorescence refers to the degree of luminescence exhibited in certain diamonds when exposed to ultraviolet light or strong sunlight. Most commonly, diamonds display a blue fluorescence, but can also appear in a variety of colours. Faint to medium fluorescence is rarely detected under ordinary lighting conditions. Strong or very strong fluorescence may make a diamond appear ‘milky’ or ‘oily’.
Fluorescence is not always a bad thing as blue fluorescence may enhance the colour of a diamond. For example, a diamond graded H with blue fluorescence may appear whiter than it really is. Fluorescence can also hide a slight yellow tint in diamonds graded I, J and K.
Fluorescence is indicated on a GIA diamond certificate and measured in Faint, Medium or Strong.
CLARITY
Clarity measures the incidence of natural inclusions or imperfections found in a diamond. The closer a diamond is to flawless, i.e.: no inclusions visible through a jewellers loupe, the more rare it is and the greater its value. Most inclusions are not visible to the naked eye, so diamonds are examined under a 10x magnifying loupe to determine their clarity.
Clarity characteristics are usually divided into two categories:
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Inclusions: imperfections that occur naturally inside the diamond itself. These were formed miles below the surface, when the diamond was formed under intense heat and pressure.
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Blemishes: imperfections that occur on the surface of the diamond and occur during the cutting and polishing process.