Learn about the importance of the 4 Cs at Ernest Jones

The 4 Cs

A diamonds value, rarity and beauty are determined by factors that are commonly known as the 4 Cs, these are: colour, clarity, carat and cut. Before deciding on purchasing your diamond jewellery, it is important to understand why two diamonds that may look exactly the same are actually valued differently. Before buying a diamond ring or jewellery, this following section will help you to understand the 4 Cs in more detail and will be useful when studying the diamond's brilliance, beauty and quality.


Diamonds naturally vary in colour with the majority of them on the market being sold as near colourless. At Ernest Jones, we use the GIA (Gemological Institute of America) scale of colour. On this scale, diamond colour is graded from D, which has the least colour, through the alphabet to Z, which has a light yellow colour. Truly colourless diamonds (D) are treasured for their rarity.

Diamonds generally have subtle differences which may not be visible to the naked eye. If you would prefer to see the difference for yourself, visit your local Ernest Jones store and speak to one of our diamond specialists. They will allow you to compare diamonds side by side.

Due to the rise in fashion-led trends, coloured diamonds are becoming increasingly more popular and valuable such as the Chocolate Diamonds by Le Vian. At Ernest Jones, we have a wide range of various coloured diamonds including black diamonds, which are natural diamonds that have been subjected to specialist treatments to enhance the depth of colour and contrast.

A diamond colour scale showing the different grades of diamond colour