4 Cs of Diamond Buying

Every diamond is regarded by nearly all of us as a valuable piece of jewellery.

In order to help us to know and understand the value of any diamond(s), the 4 Cs was created to help identify the quality and to help customers to know what they are about to purchase.

This is now globally accepted as a standard for describing or reviewing diamonds include the Colour, Clarity, Cut, and Carat Weight.

Let’s look at a bit of detail around the 4Cs as it’s called.

Diamond Colour:
A chemically pure and structurally perfect diamond has no hue, like a drop of pure water, and consequently, a higher value. The D-to-Z diamond colour-grading system measures the degree of colourlessness by comparing a stone under controlled lighting and precise viewing conditions to masterstones stones of established colour value.

Many of these colour distinctions are so subtle that they are invisible to the untrained eye; however, these distinctions make a very big difference in diamond quality and price. With some very basic information, you can quickly check the value of your diamond by using our diamond price calculator on our website. If you need to speak with someone, our in-house experts can help you to quickly identify your diamond colour so no need to worry if this all seems a bit too much.

Diamond Clarity:
The clarity of a diamond refers to the absence of inclusions and blemishes. When evaluating diamond clarity, you are determining the number, size, relief, nature, and position of these characteristics, as well as how these affect the overall appearance of the stone. While no diamond is perfectly pure, the closer it comes, the higher its value diamond cut.

The Diamond Clarity Scale has 6 categories, some of which are divided, for a total of 11 specific grades.

  • Flawless (FL)
  • No inclusions and no blemishes visible under 10x magnification
  • Internally Flawless (IF)
  • No inclusions visible under 10x magnification
  • Very, Very Slightly Included (VVS1 and VVS2)
  • Inclusions so slight they are difficult for a skilled grader to see under 10x magnification
  • Very Slightly Included (VS1 and VS2)
  • Inclusions are observed with effort under 10x magnification, but can be characterized as minor
  • Slightly Included (SI1 and SI2)
  • Inclusions are noticeable under 10x magnification
  • Included (I1, I2, and I3)
  • Inclusions are obvious under 10x magnification which may affect transparency and brilliance

Many inclusions and blemishes are too tiny to be seen by anyone other than a trained diamond grader. To the naked eye, a VS1 and an SI2 diamond may look exactly the same, but these diamonds are quite different in terms of overall quality. This is why expert and accurate assessment of diamond clarity is extremely important.

Diamond Cut:
Diamonds are renowned for their ability to transmit light and sparkle so intensely. We often think of a diamond’s cut as shape (round, emerald, pear), but a diamond’s cut grade is really about how well a diamond’s facets interact with light. 

To determine the cut grade of the standard round brilliant diamond – the shape that dominates the majority of diamond jewellery – we calculate the proportions of those facets that influence the diamond’s face-up appearance. These proportions give an indication of how successfully a diamond interacts with light to create desirable visual effects such as:

  • Brightness: Internal and external white light reflected from a diamond
  • Fire: The scattering of white light into all the colours of the rainbow
  • Scintillation: The amount of sparkle a diamond produces, and the pattern of light and dark areas caused by reflections within the diamond

The diamond cut grade also takes into account the design and craftsmanship of the diamond, including its weight relative to its diameter, its girdle thickness (which affects its durability), the symmetry of its facet arrangement, and the quality of polish on those facets.

The Diamond Cut Scale for standard round brilliant diamonds in the D-to-Z diamond colour range contains 5 grades ranging from Excellent to Poor.

Diamond Carat Weight:
Diamond carat weight is the measurement of how much a diamond weighs. A metric “carat” is defined as 200 milligrams.

Each carat can be subdivided into 100 ‘points.’ This allows very precise measurements to the hundredth decimal place. A jeweller may describe the weight of a diamond below one carat by its ‘points’ alone. For instance, the jeweller may refer to a diamond that weighs 0.25 carats as a ‘twenty-five pointer.’ Diamond weights greater than one carat are expressed in carats and decimals. A 1.08 carat stone would be described as ‘one point oh eight carats.’

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Diamond Calculator

Please provide the details below to access and open the calculator and get an instant price for your diamond and or diamond jewellery.
1. Enter Details 2. Access Calculator
3. Get an instant price

Next step: Fill in all the details below, to get an instant cash price for your diamond. Our calculator is giving prices for single diamonds only.

Click to select shape





"We will also pay you the market price for the gold or platinum in your diamond jewellery."
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