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The Four C's

The 4C's of Diamond Quality

It has been said that, 'every diamond is a miracle of time and place and chance. Like snowflakes, no two are exactly alike.' So how do you accurately determine the quality of every individual diamond?

Until the middle of the twentieth century, there was no agreed-upon standard by which diamonds could be judged. Then GIA created the first, and now globally accepted standard for describing diamonds: Colour, Clarity, Cut, and Carat Weight.

Today, the 4C's of Diamond Quality is the universal method for assessing the quality of any diamond, anywhere in the world. The creation of the Diamond 4C's meant two very important things: diamond quality could be communicated in a universal language, and diamond customers could now know exactly what they were about to purchase.

Colour

Diamond Colour actually means lack of colour. The diamond colour evaluation of most gem-quality diamonds is based on the absense of colour. A chemically pure and structurally perfect diamond has no hue, like a drop of pure water, and consequently, a higher value. GIA's D-to-Z diamond colour grading system measures the degree of colourlessness by comparing a stone under controlled lighting and precise viewing conditions to masterstones stones of established colour value.Colour

 

Cut

A diamond's cut unleashes the light

Diamonds are renowned for their ability to transit light and sparkle so intensely. We often think of a diamond's cut as shape (round, emerald, pear), but a diamond's cut grade is really about how well a diamond's facets interact with light. Precise artistry and workmanship are required to fashion a stone so its proportions, symmetry, and polish deliver the magnificent return of light only possible in a diamond. A diamond's cut is crucial to the stones final beauty and value. And of all the diamond 4Cs, it is the most complex and technically difficult to analyze.

To determine the cut grade of the standard round brilliant diamond - the shape that dominates the majority of diamond jewellery - GIA calculates the proportions of those facets that influence the diamond's face-up appearance. These proportions allow GIA to evaluate how successfully a diamond interacts withlight to create desirable visual effects such as:

Brightness: Internal and external white light reflected from a diamond
Fire: The scattering of white light into all the colours of the rainbow
Scintillation: The amount of sparkle a diamond produces and the pattern of light and dark areas caused by reflections within the diamond.

GIA's diamond cut grade also takes into account the design and craftsmanship ofthe diamond, including it's weight relative to it's diameter, it's girdle thickness (which affects its durability), the symmetry of it's facet arrangement, and the quality of polish on those facets.

The GIA diamond cut scale for standard round brilliant diamonds in the D-to-Z diamond color range contains 5 grades ranging from excellent to poor. Diamonds of Choice only offers diamonds with an Excellent to Very Good cut.

 

Clarity

Diamond clarity refers to the absence of inclusion and blemishes

Natural diamonds are the result of carbon exposed to tremendous heat and pressure deep in the earth. This process can result in a variety of internal characteristics called 'inclusions' and external characteristics called 'blemishes.' Evaluating diamond clarity involves determining the number, size, releif, nature and position of these characteristics, as well as how these affect the overall appearance of the stone, While no diamond is perfectly pure, the closer it comes, the higher its value.

Clarity example The GIA Diamond Clarity Scale has 6 categories, some of which are divided, for a total of 11 specific grades.

Flawless (FL):
No inclusions and no blemishes visible under 10x magnification
Internally Flawless (IF): No inclusions visible under 10x magnification
Very, Very Slightly Included (VVS1 and VVS2): Inclusions so slight they are difficult for a skilled grader to see under 10x magnification
Very Slightly Included (VS1 and VS2): Inclusions are observed with effort under 10x magnification, but can be characterized as minor
Slightly Included (SI1 and SI2): Inclusions are noticeable under 10x magnification
Included (I1, I2, and I3): Inclusions are obvious under 10x magnification which may affect transparency and brilliance

Many inclusions and blemishes are too tiny to be seen by anyone other than a trained diamond grader. To the naked eye, a VS1 and an SI2 diamond may look exactly the same, but these diamonds are quite different in terms of overall quality and value.

Carat

Diamond carat weight is the measurement of how much a diamond weighs

A metric "carat" is defined as 200 milligrams. Each carat can be subdivided into 100 'points.' This allows very precise measurements to the hundreth decimal place. A jeweler may describe the weight of a diamond below one carat by it's 'points' alone. For instance, the jeweler may refer to a diamond that weighs 0.25 carats as a 'twenty-five pointer.' Diamond weighs greater than one carat are expressed in carats and decimals. A 1.08 carat stone would be described as 'one carat oh eight.'
Carat Weight
All else being equal, diamond price increases with diamond carat weight, because larger diamonds are more rare and more desirable. But two diamonds of equal carat weight can have very different values (and prices) depending other factors of the diamond 4C's: Clarity, Colour and Cut.

It's important to remember that a diamond's value is determined using all of the 4C's, not just carat weight.