Understanding the Four C’s of Diamonds

Everyone talks about the “4 C’s” of diamonds, but do you know what they are and how understanding them can help you when buying a diamond engagement ring?

In the 1940s, the founder of GIA (Gemological Institute of America) developed the simple concept of the 4 C’s for his students to recall the four factors that characterise a diamond – Colour, Clarity, Cut, and Carat weight.

GIA then went on to develop the D-Z colour scale and a clarity scale, along with methods for objectively grading a diamond's quality. These methods transformed the way diamond quality is determined and communicated, becoming the universal method for assessing diamond quality. This has led to increased consistency in the diamond trade, which is great news for those interested in making their dream diamond purchase.

In this journal, we will talk you through what each of the C’s means and what you should be aware of when assessing a diamond.

Since the 1950s, diamond dealers have used a D to Z scale to describe colour in a diamond. As you move through the grades from D to Z, more of the natural tint found in white diamonds will appear in the stone, affecting its value.

The luxury brands that we sell at Xupes use only the highest quality diamonds. Engagement rings from these brands will usually be from D to J, so colourless or near colourless. Most of our engagement rings are also accompanied by diamond certificates that confirm the diamond colour.

Diamonds form in the earth when carbon is exposed to tremendous heat and pressure. During this process, they can develop internal inclusions and blemishes. Almost all diamonds will have some imperfections, and although an internally flawless diamond is considered the highest grade, these imperfections add to the uniqueness of the stone. While most inclusions are not visible to the naked eye, they can affect the flow of light through the stone, affecting its brilliance.

A diamond's clarity is measured by grading the inclusions that are visible under 10x magnification. GIA specified 11 specific grades within six categories which describe the level of imperfections.

Because the luxury brands that we sell at Xupes use only the highest quality diamonds, they tend to sit higher on the scale, with engagement rings usually graded from VS2 upwards.

We often think of a diamond's cut as its shape, but what it actually describes is how well a diamond's facets interact with light. It is the only characteristic not influenced by nature and is driven by the skill of the stone cutter.

GIA developed a standard for the ideal proportions of a brilliant cut diamond, with individual diamonds graded according to their deviation from that. The cut scale has five grades, which vary from Excellent to Poor, and it is now the definitive scale for classifying diamond cuts.

The diamond proportions are precisely mapped out and listed on both GIA and Tiffany Diamond Certificates that accompany many larger diamonds at Xupes.

Simply put, carat weight measures how much a diamond weighs. Diamonds are measured in “carats,” and each carat is subdivided into 100 points, allowing diamonds to be measured precisely. Some elongated diamond shapes like the emerald cut also maximise carat weight and can appear larger than round diamonds of equivalent carat weight in size.

The value of a diamond rises steeply as its carat weight increases because larger diamonds are much rarer. This means that, when all else is equal, a 1-carat diamond will cost more than four 0.25-carat diamonds.

Buying a diamond can be confusing, and understanding the different factors that determine the quality of a diamond will help when comparing diamonds of different qualities, understanding their price differences, and selecting the best option for your personal budget. There are often considerable savings from brand RRP when buying pre-loved, which means that when purchasing from Xupes, your dream engagement ring may be more achievable than you expect.

Our team at Xupes is always delighted to assist our clients with their engagement purchases and will be happy to talk through options either on the phone, via WhatsApp, a virtual appointment, or in our showroom where you can relax with a glass of champagne while making your special purchase.