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Purchasing a Diamond

Because diamonds are so valuable, it’s essential for industry professionals to have a universal grading system when comparing diamond quality. In the mid-twentieth century, GIA developed the International Diamond Grading System™ and the 4Cs (Cut, Clarity, Colour and Carat) as a way to objectively compare and evaluate diamonds.


The 4Cs of diamond quality will give you a multitude of information about a diamond’s characteristics and value, but they can’t begin to describe one elusive quality – beauty. To do that, you’ll need to experience the diamond with your own eyes.

Cut

The cut of a diamond refers to its proportions, workmanship and accuracy in the number of facets and their angles. This is the most important aspect of a diamond's brilliance and sparkle. Of the 4 C's, the cut is the aspect most directly influenced by human involvement.
Diamonds are generally cut with 58 separate flat surfaces, or facets. These facets are placed at precise angles in relation to each other, according to a mathematical formula. This relationship is designed to maximize the amount of light reflected through the diamond and to increase its beauty.

Diamonds are cut into various shapes depending upon the original form of the uncut diamond, which is referrred to as `rough`. Whatever the shape, a well-cut diamond is better able to reflect light and therefore sparkle more.
If the pavilion angle is cut too deep, the diamond will be darker than is optimal. If the cut is too shallow, the stone will be too light and clear. The key to a well-cut diamond is finding this balance for the perfect fit.

Clarity

Almost all diamonds have tiny inclusions that can greatly affect the value and beauty of a stone. These 'birthmarks' are unique, and for the most part, the fewer the imperfections, the rarer and more valuable the diamond. In addition to internal inclusions, surface irregularities are referred to as blemishes. These internal and external imperfections are what make up the clarity of a diamond.
Clarity is graded using a very precise and complex method of evaluating the size, location, adn visibility of inclusions. For the untrained eye, it is rare that imperfections be seen for an unmagnified eye until the I1 or I2 range. The key to deciding on clarity, is to determine what level of perfection is important to you.

Colour

In terms of colour, diamonds are graded from D, which is colourless- the absolute finest colourless stone- descending through each letter of the alphabet to Z, a diamond of dull yellow, brown, or gray. This GIA scale is universally accepted, and as the body colour becomes more intense, the grade for colour descends the scale. Diamonds with a high colour rating a more beautiful and rare, and this is why they are much more valuable.
When directly comparing diamonds for colour, many consumers alone are unable to detect a difference unless they are at least two or three colour grades apart. At Rasko Diamonds, we will show you how to view the exact differences between colours and will provide an independent, objective certificate of appraisal to ensure quality control.

Carat

A diamond's weight is measured in carats. One carat is standardized at 0.2 grams, and one carat is divided into 100 points. A diamond weighing one quarter of a carat can also be described as weighing 25 points, or 0.25 carats.
Larger diamonds are usually rarer, and thus more valuable than smaller ones. Moreover, two individual diamonds weighing the same as one larger one may not be as valuable, because of the greater rarity and difficulty of mining the larger stone.