All you need to know about the ‘4Cs’ (colour, clarity, carat, and cut) to make that all-important decision
There is no more significant jewellery purchase than an engagement ring. It is, after all, a declaration of love and a long-standing symbol of commitment. Therefore, getting it right is vitally important, and when selecting a stone, the 4Cs – cut, colour, clarity, and carat – can provide an excellent reference point.
Here’s our no-nonsense guide to choosing the best diamond depending on individual preferences and budget.
Cut
In the realm of natural diamonds, cut is the only aspect of the four Cs that is not influenced by nature. Instead, it falls on craftmanship. One might assume ‘cut’ refers to the shape and size of the diamond; it is, however, indicative of how a stone is faceted, proportioned, and polished.
A key aspect of cut is how the diamond interacts and disperses light. This ultimately influences the attractiveness of a stone and the extent of its sparkle.
According to the Gemmological Institute of America (GIA), which devised the 4Cs as a global industry marker of gem quality, standard round brilliant cut diamonds in the D-to-Z colour range are assessed in three areas.
Face-up appearance, i.e, how it is viewed from above, analyses the diamond’s ‘brightness’ – the total internal and external reflection of white light; ‘fire’ – the dispersion of light into colours of the spectrum; and ‘scintillation’ – the pattern of light and dark areas, and the diamond’s sparkle as it moves. Design and craftsmanship, meanwhile, evaluate the quality of the diamond’s manufacture.
A diamond’s beauty is very much dependent on cut. A poorly cut diamond will appear dull, even if it boasts excellent colour and clarity. Meanwhile, a well-cut diamond will transform white light into a beaming, radiant prism of colour.
It’s worth noting that only round brilliant cut diamonds are graded by cut because they have standardised facets. Any other shape – marquise, pear, ovel, emerald, heart and triangle – fall under ‘fancy shapes’ and outside the remit of this category. Nonetheless, it’s still crucial to consider polish and symmetry grades, etc if purchasing fancy shaped diamonds.
Colour
White diamonds come in many shades, ranging from colourless to warm white to gems with hints of yellow. They are graded on a scale from D to Z (colourless to light), with Grade D considered the rarest and bearing the least colour. This scarce grade of diamonds appears colourless to the naked eye and, even when viewed under magnification. Diamonds of such, or similar calibre, should always be set in platinum or white gold so as not to detract from their incredible icy brilliance.
Clarity
Clarity is the measure of a diamond’s purity. Birthed in the earth’s crust, it isn’t unusual for diamonds to contain what the GIA refers to as birthmarks. These occur when tiny crystals are trapped in the diamond as they grow under tremendous heat and pressure. Minor marks or flaws can form, including feathery cracks, ‘twinning wisps’, dark spots, and white points, many not visible to the naked eye.
The size, location, visibility, and number of inclusions or blemishes are studied under a microscope. Internal and surface-reaching imperfections within the diamond are known as inclusions, while external markings are called blemishes and are often caused during the cutting process. These characteristics can impact how light is reflected and refracted.
Gems with fewer inclusions and blemishes are deemed higher clarity. Rated on an eleven-grade system (FL, IF, VVS1, VVS2, VS1, VS2, SI1, SI2, I1, I2, and I3); a rare, flawless diamond would receive an (FL) clarity grade, while a diamond with obvious inclusions may receive a clarity grade of I3. The latter might have questionable transparency, brilliance, and durability.
Store-bought diamonds broadly fall between VS (very slightly included) and SI (slightly included) on the clarity scale. If flaws aren’t visible to the naked eye, they’re called ‘eye clean diamonds’. With this in mind, buyers should consider whether it’s worth paying additional money for better clarity and colour if the variance is only noticeable when the stone is examined under a microscope.
Carat
The fourth and final C refers to ‘carat’. This is not a direct measurement of a diamond’s size as people often assume, but its mass/weight. One carat equates to 200 milligrams. Carat alone doesn’t determine the value of a diamond, since all the other Cs are influencing factors.
Some diamond shapes appear more prominent despite being the same mass. Elongated with both ends tapered in points, the marquise diamond creates the largest surface area and has the largest appearance of all gem shapes. More so than oval and pear.
How the diamond is cut can also impact the size. Poorly cut diamonds that change in depth or feature a thick girdle – the part of a diamond that separates the crown (top) from the pavilion (bottom) – weigh more but look smaller because their weight sits in the base of the diamond. Consequently, there is less surface area on top, which makes a diamond appear smaller and sparkle less.
Thus, a larger carat doesn’t always mean a larger diamond. We suggest trying different carats and shapes to better understand your preferences.
To Conclude
While the 4Cs are the global standard for assessing the quality of a diamond, they are just a guideline. They can, however, help buyers understand how each factor influences the appearance and price of a diamond.
Cut is considered the most significant of all the Cs because it truly influences the beauty and sparkle of a diamond. A well-cut diamond will not only make the stone appear bigger and brighter but also ensure colour and clarity imperfections are less discernible.
Together, the 4 Cs merge to establish a diamond’s value, and the importance of each varies from person to person. While some may rate size over clarity, others seek out an excellent cut for its spectacular sparkle.
When purchasing natural diamonds, there will always be slight imperfections and compromises. it’s about choosing one that feels right to you—flaws and all.