4 C's of Diamonds
ColourDiamonds are classified as either “white” or “fancy.” A fancy diamond is one whose colour is vibrant enough that it must be classified on its own terms, and white diamonds are supposed to be as clear as possible.
However, while diamonds composed solely of carbon are completely clear, very few of them fall into this category. Being formed by natural processes rather than in a sterile laboratory where materials can be scientifically controlled, diamonds usually have foreign material trapped in them during their formation. The most common of these substances is nitrogen gas, which gives diamonds a yellow or off-brown colour. Because nitrogen is so prevalent on Earth, most diamonds will have some degree of nitrogen in them, making truly colourless white diamonds very rare.
The GIA categorization for white diamond colour begins with “D” and goes to “Z,” with D representing an utterly colourless diamond and Z reserved for extremely tawny yellow stones.
CutCarat is usually mistaken for “size,” but like grams, “carat” is used to describe the weight of a diamond. One carat weighs exactly 0.2 grams, and there are 100 points in each carat. Thus, if a carat were described as 4.72 carats, it could also be described as 472 points or 0.944 grams.
And because carat is not synonymous with size, diamantaires experiment with different shapes of diamond that may contain the same weight while having radically different volumes. For example, a 2-carat round-cut diamond may have the same weight as a 2-carat emerald-cut diamond, but the latter will appear much longer on a woman’s finger thanks to the way the weight of the stone is distributed.
Carat WeightAs with carat, “cut” is usually mistaken for the shape of a diamond. While the two ideas are related, they aren’t the same. Diamantaires have determined that each shape of diamond (such as round, emerald, and heart shapes) has an ideal set of dimensions to maximise the way the stone captures light. These proportions are very exacting, and even slight deviations from the pattern can cause an otherwise lovely diamond to appear as dull and dark as a pebble. The quality of a diamond’s cut is not to be understated for the woman who adores the fire and scintillation of the unique jewel.
The GIA classifies cut according to its own standards, with the scale going from “excellent” to “poor.” The system uses a seven-point scale to grade the way diamonds have been cut: brightness, fire (the rainbow effect of a diamond), scintillation (flashes of white light), weight ratio, polish, symmetry, and durability.
ClarityNitrogen gas isn’t the only thing that can be captured by melted carbon during the birth of a diamond. The same natural processes that affect colour also affect the flawlessness of a diamond.
Disruptions that change the natural flawlessness of a stone are known as “inclusions” and can range from breaks in the crystal of a diamond, such as bubbles, cracks, voids, and other irregularities to foreign material being trapped in the stone’s lattice. The most common foreign materials trapped inside diamonds include black carbon, sand, small garnet crystals, and iron specks. Inclusions aren’t rare in diamonds, but as they become bigger or more numerous, they can negatively impact the way light travels through a stone, making a diamond less beautiful.
The GIA standard scale for clarity goes from F (flawless) to I3 (extremely visible inclusions). This standardized grading scale requires a skilled grader, who uses a 10x magnification loupe to determine the location, density, and visibility of any inclusions—including those that may not be visible to the naked eye.