The 4 C's OF Diamonds

THE 4 C’S of diamonds




Cut - How the diamond is cut.

Colour - The colour of the diamond or how colourless it is.

Clarity - The presence of inclusions / natural imperfections within the diamond.

Carat - How much the diamond weighs.


These 4 C’s determine the value and beauty of a diamond.

Two diamonds may look the same, but depending on the carat weight, cut, colour and clarity grading of each, they could be valued extremely differently.


In order, with most important first:

1. CUT

The Cut of a diamond is the most important of the 4C’s because it has the biggest influence on the bling and sparkle of the diamond.


The Colour of a diamond comes in second for importance because the less colour, the higher the diamond is graded.


The Clarity of a diamond comes in at third because this refers to imperfections within the diamond, but these are often only visible under 10x magnification.


The Carat weight of a diamond comes in fourth because this has no bearing on the quality of a diamond - A 6-carat diamond may be worth less than a 3-carat diamond if it is worse quality. Choosing your ideal carat weight will depend solely on how heavy you would like your ring to be.



The Shape of a diamond has no impact on the quality of the diamond. Choosing your ideal diamond shape usually comes down to style, though some shapes can be cut to a brilliant style, creating more sparkle.


Some people value diamond certification highly, but if you buy from a trusted diamond retailer, the certification of a diamond is usually considered the least important factor. Although it can be a nice addition to your confidence in your purchase, certification is not a necessity for diamonds. And all diamonds brought into England must comply with the Kimberley Process - an international certification scheme that regulates trade in rough diamonds. It aims to prevent the flow of conflict diamonds, while helping to protect legitimate trade in rough diamonds.


How the diamond is cut.

As stones, diamonds are mined rough (shapeless). A diamond cutter then assess the stone and determines how best to cut it. The cut chosen depends on the individual stone, its clarity and colour. Most cutters will cut a diamond to an ideal standard, this means that the proportions are in line to maximise the fire and brilliance.

A diamond is cut by polishing flat surfaces into the stone. These are called Facets. If a diamond has been cut to proportion correctly, the light drawn in will reflect and bounce from one facet to another - This is what gives the diamond its brilliance and fire.

A common mistake you'll come across in the diamond industry is the thought that Cut = the shape of a diamond. This is wrong. Two diamonds can have the same cut, yet be completely different shapes.

The Cut of a diamond is extremely important as this can determine:

  • Show - A diamond can be cut to maximise the impact that it has when viewed within its setting.
  • Visibility - Diamonds can be cut to minimise or hide inclusions (imperfections) but these will still be visible when graded or viewed under 10x magnification.
  • Sparkle - Symmetry, proportion and polish-finish of a diamond will determine the quality of the cut.

This is why the cut quality is incredibly important to consider when buying a diamond.


The colour of the diamond, or how colourless it is.

Diamonds are stones that are mined from the ground. So variances between each diamond are common. One of the easiest differences to the naked eye is the colour, or lack thereof.

When diamonds are submitted to Gemologists, they compare these to an internationally accepted master set of stones in order to determine the colour. The scale descends from D - Colourless, to Y - Light Yellow.

Any stones graded Z, or are deeper coloured, or in other shades such as orange, pink, blue, black, etc., are classed as "Fancy Coloured Diamonds" and are graded and priced according to a separate scale.

The colour doesn't necessarily affect the value of an individual diamond. Though it's generally accepted that the colourless range D-F are the most expensive and rarest of the standard colour scale.


Inclusions / natural imperfections within the diamond.

As with all natural stones, the majority of diamonds have imperfections. The less imperfections, the higher the clarity of the diamond, and the higher its worth.

Imperfections found in diamonds are not necessarily what you’d think either. Some say they look like smaller gems or even feathers.

Gemologists examine diamonds under 10x magnification and determine the clarity of a diamond according to a Clarity Scale that descends from FL to I3.

Inclusions on the lower end of the scale can sometimes be seen by the naked eye.

  • FL – Flawless
  • IF – Internally Flawless
  • VVSI1 and VVSI2 – Very Very Slightly Included
  • VS1 and VS2 – Very Slightly Included
  • SI1 and SI2 – Slightly Included
  • I1, I2 and I3 – Included


How much the diamond weighs.

The carat of a diamond only refers to its weight, it does not determine the size of the diamond. So a diamond with a large show, may have a low carat-weight, and vice versa.

It’s common that in a ring with more than one diamond, the carat weight will refer to all the diamonds collectively. So, a ring with a centre stone of 2-carats and two singular 1-carat diamonds set into the shoulders would be considered a 4-carat ring.


Carat is derived from Carob seeds, which were originally used by traders in the Middle East due to their uniformity of weight, each seed weighing almost exactly 0.2 grams. So 1 carat = 0.2 grams.

Carats also work on a point system. 100 points = 1 carat.
So, 50 points = 0.50-carats, 75 points = 0.75-carats, 200 points = 2 carats, and so on.


We get that buying diamonds isn’t fun when you don’t know what you’re looking for. But now that you’re a pro in the 4 C’s of diamonds, why not check out our range of diamond rings by clicking here. Or, if you’d like more inspiration, have a look at our other diamond blogs below.

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MJJ Engagement Rings

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