4C's of Diamond
Before the mid-twentieth century, there was no consensus on how diamonds should be evaluated for their quality. However, the Gemological Institute of America (GIA) established the first globally accepted standard for describing diamonds, the 4Cs of Diamond Quality.
This standard assesses a diamond’s colour, clarity, cut, and carat weight. Today, the 4C’s remain the universally recognised method for evaluating the quality of any diamond, regardless of its origin.
The Diamond 4C’s had a significant impact for two critical reasons.
Firstly, it allowed a universal language to communicate diamond quality transcending geographical boundaries.
Secondly, arguably more importantly, it gave diamond customers the confidence to know precisely what they were purchasing. This development was a game-changer in the diamond industry.
Colour
Diamond colour is distinct from the spectral colours that flash when a diamond is in motion; it refers to the stone’s inherent body colour.
Typically, diamonds have slight tinges of yellow, brown, or grey due to natural trace amounts of nitrogen during the diamond’s formation beneath the Earth’s crust. A less colourful diamond is considered rare and, therefore, more valuable.
Diamond Colour
The colour of a diamond is determined by its composition and remains constant over time. Colourless diamonds allow light to pass through, resulting in greater fire and sparkle than their coloured counterparts.
A diamond’s colour is determined by the process of its formation. A whiter diamond will fetch a higher value, and jewellers typically use the GIA colour scale to grade diamonds, beginning with D for the most colourless and progressing to Z as yellow or brown hues become more prominent.
Diamonds graded from D to F are highly sought-after and valuable, but those with lower grades can still be of good quality and appear colourless to the untrained eye, making them a more affordable option.
Diamond enthusiasts will surely find much to appreciate in both high and low-priced diamonds.
Clarity
Clarity of a diamond refers to how clean and clear it is, taking into account any microscopic natural characteristics that may have been trapped inside or on the diamond during its formation.
These characteristics can appear inside the diamond as inclusions or on the surface as blemishes. Inclusions may be foreign material crystals or structural imperfections like tiny cracks known as feathers, which may appear whitish or cloudy.
Diamond Clarity
When it comes to diamond clarity, it’s all about identifying the blemishes and inclusions present in the gemstone. Considering the extreme pressure under which diamonds form and the fact that they aren’t created in sterile labs, it’s no surprise that most diamonds have flaws. These flaws come in two types: blemishes and inclusions. Inclusions refer to naturally occurring internal flaws such as cracks, air bubbles, or minerals, while most blemishes occur during the cutting process.
The more flawless a diamond is, with fewer blemishes and inclusions, the more valuable it’s considered. GIA certificates come with a diamond inclusion plot, ensuring the uniqueness of each diamond. This plot assures the buyer that the diamond they receive is the one they paid for. Flawless is the rarest and highest clarity grade for those unsure about what clarity grade to choose.
Cut
The cut of a diamond isn’t about its shape, but rather the balance of proportion, symmetry, and polish achieved by the diamond cutter. How well a diamond is cut determines its overall beauty.
A well-cut diamond can significantly enhance its ability to reflect and refract light. Diamond cutters have studied how light travels through diamond crystals, enabling them to establish specific proportions and angles that bring out a diamond’s internal brilliance and showcase it in the best light possible.
Ideal Cut
An Ideal Cut Diamond is a round, brilliant, or princess cut diamond that’s cut with perfect proportions and angles, featuring excellent polish and symmetry ratings. Such diamonds are perfectly balanced to refract light, producing that dazzling fire and brilliance that emanates from the table and crown.
GIA, one of the most reputable laboratories for grading natural diamonds, uses a grading system on their certificates to assess the cut of round diamonds.
The grading ranges from Excellent, Very Good, Good, and Fair, to Poor. A GIA Excellent cut is classified as either Ideal or Super Ideal, based on specific diamond characteristics such as cut grade, polish, and symmetry.
For fancy-shaped diamonds, where the cut grade isn’t available from a grading laboratory, we use factors like depth, table, secondary measurements, and subjective factors to evaluate the cut grade of the diamond.
Carat
Carat (ct.) is a distinctive unit of weight measurement used solely for weighing diamonds and gemstones. Despite this, carat weight is often mistakenly equated with visual size. The weight of a gemstone will appear differently depending on its shape and type.
For instance, a 1.00 ct. round diamond will measure approximately 6.5mm, while a 1.00 ct. round sapphire will measure around 6.0mm. This difference is caused by the differing densities of various gemstones.
Carat Weight
When it comes to diamonds, carat weight is one of the four Cs (along with color, clarity, and cut) that are used to determine a diamond’s value. In general, larger diamonds are rarer and more valuable than smaller diamonds, all other factors being equal. For example, a 2-carat diamond will be worth more than two 1-carat diamonds of equal quality. However, larger diamonds are also more difficult to find and more challenging to cut, which can affect their value.
It’s important to note that carat weight is not the same as diamond size. The size of a diamond is influenced by its shape, cut, and carat weight, as well as other factors such as its depth and girdle thickness. In general, a diamond with a higher carat weight will be larger than a diamond with a lower carat weight, but this is not always the case. For example, a diamond with a shallow cut may appear larger than a diamond with a deeper cut, even if the two diamonds have the same carat weight.