The Four Cs: Cut, Carat, Colour and Clarity
The four Cs – cut, carat, colour and clarity – are the best-known factors used to describe and assess a diamond. They are important indicators of quality and value, but they do not tell the whole story.
A grading report from a gemmological laboratory records measurable characteristics, but a diamond's beauty cannot always be understood from its grades alone. There are nuances within every grade, which means that two diamonds with seemingly identical specifications can look remarkably different when viewed side by side.
This is why we believe a diamond should be seen, not simply read about on a certificate.
How to Choose the Right Diamond
There is no single combination of characteristics that is right for everyone. The qualities you choose to prioritise should reflect what matters most to you.
Some prefer a larger diamond and are comfortable choosing a slightly lower colour or clarity grade. Others are drawn to warmer tones, while some prefer a diamond that appears as colourless as possible. This is where experience and specialist knowledge become particularly valuable. At Langaard, we help you balance your preferences, priorities and budget to find the diamond that is right for you.
Ultimately, what matters most is how you experience the diamond – its beauty, brilliance and the way it interacts with light. For this reason, we recommend looking at several diamonds side by side rather than choosing from a certificate alone. Comparing them in person gives you a far better understanding of their individual character.
We also recommend booking an appointment with our gemmologist, who can guide you through the different quality factors and help you understand where the differences matter most.
A piece of diamond jewellery is more than a purchase. It can mark a moment, represent someone you love and, with the right choice, become part of a story that continues for generations.
Carat
Carat measures a diamond's weight, not its physical size. One carat is equal to 0.20 grams.
Diamond prices do not increase in direct proportion to carat weight. A 2.00 ct diamond is considerably rarer than a 1.00 ct diamond and can therefore be worth more than twice as much, assuming the other quality factors are comparable.
Although carat is often associated with size, two diamonds of the same carat weight can have different dimensions. Their proportions and cut affect diameter, depth and how large the diamond appears when viewed from above.
The diamond market also has important weight thresholds, sometimes referred to as “magic sizes”. At sought-after weights such as 1.00 ct, 1.50 ct and 2.00 ct, rarity increases and prices can rise noticeably.
For this reason, carat weight should always be considered alongside proportions, cut and the overall appearance of the diamond.
Cut
Cut is one of the most important factors in how a diamond looks. It determines how effectively the diamond captures and reflects light, and has a direct impact on its brilliance and fire. Even a diamond with high colour and clarity grades can appear dull if the cut is poor.
Cut quality is assessed through the diamond’s proportions, symmetry and polish. Together, these determine how light travels through the stone and how much is reflected back to the eye. When the proportions are well balanced, the diamond makes better use of the light that enters it, creating greater brilliance and sparkle.
A diamond with an Excellent cut grade meets strict criteria for proportions, symmetry and polish. With a less precise cut, more light can escape through the sides or bottom of the diamond instead of being reflected back, making it appear less brilliant.
For this reason, we recommend giving cut particular attention when choosing a diamond. A beautifully cut diamond can make a greater visual difference than moving slightly higher in colour or clarity.
Diamond Shapes
The round brilliant is the most popular diamond shape and is generally regarded as the shape designed to return the greatest amount of brilliance to the eye.
Other popular shapes include:
• Oval
• Cushion
• Princess
• Emerald
• Pear
Shapes such as oval and pear can appear larger than their carat weight might suggest because of the way their surface area is distributed.
The shape and facet pattern can also influence how readily inclusions can be seen. In shapes with fewer, larger facets, such as an emerald cut, inclusions may be easier to notice. This is one reason why the different quality factors should be considered in relation to the individual diamond rather than in isolation.
Colour
Very few natural diamonds are completely colourless. Most contain subtle traces of colour, usually yellow or brown. Within the traditional colourless diamond scale, the less colour a diamond displays, the rarer – and generally more valuable – it becomes. Even subtle differences in colour can influence both appearance and price.
The internationally recognised GIA colour scale runs from:
D – Colourless
to
Z – Light yellow or brown
Traditional trade terms are also sometimes used:
River – D–E
Top Wesselton – F–G
Wesselton – H
Choosing the Metal
The metal surrounding a diamond can influence how its colour is perceived. White gold and platinum create a bright, neutral setting that complements diamonds in the higher, more colourless grades.
Diamonds further down the colour scale may show warmer yellow or brown tones. In these cases, yellow or rose gold can be a particularly good choice. The warmer colour of the metal creates less contrast with the diamond and can make its natural warmth appear more subtle.
Colour also tends to become more noticeable in larger diamonds and in cuts with fewer, larger facets, where there is less sparkle to disguise subtle differences in tone.
Champagne Diamonds
Champagne diamonds are known for their warm colour, ranging from pale champagne to deeper cognac tones. These colours pair particularly well with yellow and rose gold, where the warmth of the metal complements the natural colour of the diamond.
Champagne diamonds are generally priced below comparable colourless diamonds, making it possible to choose a larger stone at a more accessible price.
Black Diamonds
Black diamonds are known for their deep, intense colour, which is typically associated with a high concentration of natural inclusions. Many black diamonds on the market are also treated to enhance the depth and uniformity of their colour.
Unlike colourless diamonds, black diamonds are opaque, so light does not pass through them in the same way. Instead, light is reflected from the surface, giving the stone its characteristic lustre. The result is a bold expression that creates a striking contrast with both precious metals and colourless diamonds.
Naturally Coloured Diamonds
Beyond the traditional colour scale are naturally coloured diamonds, some of the rarest diamonds in the world. They occur in colours including yellow, pink, blue, green and red.
Their value is determined largely by the rarity and intensity of the colour. Certain colours are exceptionally scarce, and larger examples can be so rare that they are most often seen at major international auction houses.
Clarity
Clarity describes the natural inclusions and internal characteristics found within a diamond. Almost every natural diamond carries traces of the conditions in which it was formed deep within the Earth. These can include tiny mineral inclusions, growth patterns and small fractures. Diamonds with no visible inclusions or blemishes are exceptionally rare.
When a diamond is graded for clarity, the number, size, type, position and visibility of its inclusions are all taken into account. The clarity scale ranges from FL (Flawless) to I3 (Included).
In diamonds graded SI1 or higher, inclusions are often not visible to the naked eye. This is why we recommend looking at the diamond itself rather than judging it by the clarity grade alone.
At Langaard, we do not necessarily see natural inclusions as imperfections. They are part of the diamond’s natural formation and contribute to the individual character of each stone. What matters is where the inclusions are located, how visible they are and whether they affect the beauty or integrity of the diamond.
Some inclusions require closer consideration. Those that reach or extend towards the surface can, depending on their size and position, affect the durability of the diamond. This is particularly important for jewellery such as rings and bracelets, which is more exposed to knocks and everyday wear.
The Kimberley Process
The Kimberley Process Certification Scheme (KPCS) was established in 2003 to prevent conflict diamonds from entering the international trade in rough diamonds. The scheme sets requirements for the certification and international trade of rough diamonds and today covers the vast majority of global rough diamond production.
More than 99% of the world’s rough diamonds are traded within the Kimberley Process framework. While the scheme continues to evolve, it remains the principal international framework for preventing conflict diamonds from entering the legitimate rough diamond trade.
At Langaard, we source diamonds exclusively from established and reputable suppliers who adhere to the requirements of the Kimberley Process and applicable international standards for responsible diamond sourcing.
