The 4 C's...
The value of a diamond is determined by four characteristics known as “The 4 C’s”
One carat is divided into 100 points. Therefore a diamond of a quarter carat is generally known as a “25- pointer”. The size of a diamond is indicated as two decimal numbers after the point, folloswed by the letters ct. (e.g. 0.15ct or 1.25 ct). Size is an important factor in determining the value of a diamond. However, two diamonds of equal size can have different values, depending on their quality.
Most people are surprised that diamonds can be found in all colours. The most common colours range from a pale yellow to the rare ‘colourless’ white. The colour of a diamond is indicated by a letter, ranging from A to Z. The finest white available for general commercial use, normally range from D to F. Slightly tinted can be from K to M and light yellow from S to V and so forth.
This is the one ‘C’ which is determined by the cutter’s skill and not by nature. It is the cut that enables the diamond to make the best use of light and it has a significant influence on the price of a diamond. Cutting a jewellery quality diamond from a rough stone is an art in its own right and a very complex process. Each of the tiny facets must be perfectly fashioned so as to best reflect the incoming light. When a diamond is cut to the perfect proportions (every facet must be in proportion to the diamond as a whole and in perfect relation to the next one), all the light entering the diamond from any direction, is totally reflected through the top. This is what gives a diamond its lively sparkle!
Almost all diamonds contain minute traces of non-crystalized carbon. These, known as inclusions are what make every diamond unique. In gem quality diamonds, the inclusions are not obvious to the naked eye and will only be visible if magnified, at least, 10 times. A diamond with fewer inclusions will be more valuable. Clarity is indicated by the following descriptions: Very, very slightly included (VVS1 & VVS2), Very slightly included (VS1 & VS2), slightly included (S1 & S2) and piqué (I1, I2 & I3)