The 4 C's of Diamond Value
Cut - Of all the 4C's, cut is the aspect of most directly influenced by man. The other three are dictated by nature. Diamonds are cut into a number of shapes, depending on the nature of the rough stone. The cut or make of a diamond wi dramatically influence its fire and sparkle, for it is the cutter's skill that releases its beauty. It is the cut that enables a diamond to make the best use of light.
When a diamond is cut to good proportions, light is reflected from one facet to another and then dispersed through the top of the stone or bottom. If the cut of the diamond is too deep, some light escapes through the pavilion before it can be reflected.
Color - Although the majority of gem diamonds appear to be colorless, others can contain increasing tinges of yellow or brown, some of which are referred to as champagne diamonds. It is a totally colorless diamond that allows blue, pink or amber - are now as "Fancies."
The color grading scale ranges from totally colorless to light yellow The differences between one grade and another are very subtle, as can be seen by the number of grades within any one category.
Clarity - almost all diamonds contain minute traces of non-crystallized carbon or small non-diamond crystals. Most are not discernible to the naked eye and require magnification to become visible. Called inclusions, they are nature's fingerprint and make every diamond unique. The minute inclusions neither mar its beauty nor endanger its beauty; however, the fewer there are, the rarer the stone will be.
Carat-Weight - As with all precious stones, the weight - and therefore the size - for a diamond is expressed in carats. The word carat is derived from a traditional system of weighing diamonds in comparison to the seeds of a carob tree. Diamonds were weighed against these seeds, however, the system was later standardized and one carat was fixed at 200 milligrams (1/5 of a gram).
One carat is divided into 100 "points" so that a diamond of 25 points is described as a quarter of a cart or 0.25 carats. Size is the most obvious factor in determining the value of a diamond, but two diamonds of equal size can have unequal prices, depending on their quality. And diamonds of high quality can be found in all size ranges.