By Jen Hui Chen
Carat, Color, Clarity and Cut ( 4C's )
The Factors Influencing a Diamond's Value. The Carat, Color, Clarity and Cut are the major and important components of a diamond.
Normally a good number of people not spending their time in reviewing these components while purchasing a diamond, this may bring them to a false conclusion on buying a low quality diamond without their knowledge.
It is important for every buyer that they should have prior knowledge on these 4C’s before going to purchase a diamond.
Carat, Color, Clarity and Cut ( 4C's )
The Factors Influencing a Diamond's Value. The Carat, Color, Clarity and Cut are the major and important components of a diamond.
Normally a good number of people not spending their time in reviewing these components while purchasing a diamond, this may bring them to a false conclusion on buying a low quality diamond without their knowledge.
It is important for every buyer that they should have prior knowledge on these 4C’s before going to purchase a diamond.
When selecting a diamond, most jewellers refer to the 4 C’s:
- Carat or weight
- Color
- Clarity
- Cut
These four factors largely determine the value of a diamond.
Diamond Carat or Weight
Carat is not a measure of a diamond’s size, but rather a measure of a diamond’s weight.The weight of diamonds is measured in ‘carats’ (often abbreviated to ‘ct’), with diamonds being available in various weights and fractions of a carat. One carat is divided up into 100 points such that 0.75 carat is the same as ¾ carat.The word carat is derived from the carob tree or Ceratonia Siliqua, which produces seeds of high uniformity and consistent weight. Diamonds and other gemstones were originally weighed against these seeds. More recently, one carat (or 100 points) has been standardised at 0.2grams. Don’t confuse carat with karat, as in “18K gold,” which refers to gold purity.
While size is a major determining factor in the price of a diamond, quality can also play a significant role. It should also be noted that the larger a diamond, the rarer it is, which will also have a bearing on its value.
The most important thing to remember when it comes to a diamond's carat weight is that it is not the only factor that determines a diamond’s value. The diagram to the right shows the size of various carat weights of a diamond in relation to each other.
Carat Weight Scale
Diamond Color
The colour of diamonds is determined by the presence of trace elements present in the atomic structure of the diamond. The more intense the colour, the further the grading descends down the scale.
Diamonds come in a range of colours from faint yellow or brown, through to very rare pinks, blues, greens and other colors known as fancies. The best colour for a diamond is no colour, i.e. a diamond that allows white light to pass through it effortlessly and be dispersed in a rainbow of colors.
Acting as a prism, a diamond can divide light into a spectrum of colors and reflect this light as colorful flashes called fire. The less color in a diamond, the more colorful the fire, and the better the color grade.
The best colorless stones carry a grading allocated ‘D’. From here, grades are designated letters ranging all the way through the alphabet down to Z, for diamonds which may be light yellow, brown or grey. Color grading's are difficult compare/determine without the correct conditions and equipment.
Diamonds are graded on a color scale established by the Gemological Institute of America (GIA), which ranges from D (Colorless) to Z.
Diamond Color Scheme
Almost all diamonds contain inclusions (often called birthmarks) which affect its clarity. There are an internal flaws or inclusions. External flaws also exist and may consist of surface irregularities or blemishes which also affect clarity.
Inclusions are natural identifying characteristics such as minerals or fractures, that appear while diamonds are being formed. They may look like tiny crystals, clouds or feathers. Inclusions are usually viewed at 10x magnification.
Grade a diamond’s clarity according to the GIA International Diamond Grading System. The GIA Clarity Scale has a range of 11 grades that run from flawless (FL) to obvious inclusions (I3). A diamond that is higher up on the Clarity Scale will be more brilliant – and with all other characteristics being equal, more valuable – because it doesn’t have inclusions and/or blemishes that impede its ability to refract and reflect light.
Clarity Grading Scale
Classification | Description |
Flawless and Internally Flawless F1 & FL | Flawless is the highest grade. These diamonds contain no detectable flaws when viewed with a microscope at 10x magnification. Internally flawless diamonds contain no visible internal flaws when viewed with a microscope at 10x magnification, but have minor surface blemishes. |
Very Very Slightly Included VVS1 & VVS2 | The classification is divided into 2 categories. They contain minute inclusions often only seen by experienced graders under a microscope at 10x magnification. |
Very Slightly Included VS1 & VS2 | Again, this category is divided into 2 categories. They contain slight imperfections which are still difficult to detect under a microscope. |
Slightly Included SI1 & SI2 | Also divided into 2 categories. These diamonds contain slight imperfections that can be seen under a microscope at 10x magnification. |
Include I1, I2 & I3 | This category is divided into 3 classes, with increasing number indicating flaws that are more obvious, with some being visible to the naked eye. |
Diamond Cut
A diamond’s cut is the most critical of the 4Cs because it’s what gives the diamond its brilliance, sparkle, and fire – the diamond’s three main attributes. When people talk about “brilliance,” they are referring to the amount of light a diamond reflects. “Fire” describes the way the light disperses and how the diamond shows off the different colors of the spectrum. “Sparkle” – also known as “scintillation” – defines how much the diamond shimmers when you move it around in the light. When light enters the diamond, it is refracted and bounces back out in a rainbow of colors.
The cut of a diamond determines its brilliance. There is no single measurement of a diamond that defines its cut, but rather a collection of measurements and observations that determine the relationship between a diamond's light performance, dimensions and finish. Most gemologists consider cut the most important diamond characteristic because even if a diamond has perfect color and clarity, a diamond with a poor cut will have dulled brilliance.
The Effect of Cut Quality on Light Refraction
Too Shallow - Light is lost out the bottom.
Too Deep - Light escapes out the sides.
Ideal Cut - Maximum provides sparkle in a diamond
Too Deep - Light escapes out the sides.
Ideal Cut - Maximum provides sparkle in a diamond
Proportion
An Ideal cut has a specific set of guidelines defining the proportions that give a diamond the highest level of fire and brilliance. It takes into account the relationship between the table size, crown angle, pavilion angle, girdle, crown depth and pavilion depth. It evaluates the following:
the size of the table (flat surface) relative to the stone’s width at its widest point, called the girdle
the angles of all facets relative to one another
the depth of the crown vs. the pavilion and how well the facets at the crown (top) align with the pavilion (bottom).
The following diagram outlines a diamond's basic proportions:
Diamonds are usually cut with 58 flat surfaces of facets. The size and location (in relation to other facets) are determined by a precise mathematical formula, designed to maximise a diamonds’ brilliance.
Some common cuts of diamond include: Round, Princess, Oval, Marquise, Emerald, Heart.
The most important factors in choosing a diamond stone is deciding on the shape that perfectly matches your style and looks beautiful on you. Your style may guide you to more traditional shapes such as the classic Round, Emerald or Asscher cuts or fancy shapes such as the Marquise, Heart or Pear.
