fancy coloured diamonds

There are a range of colours that natural diamonds can be found in, albeit rarely. These colours can assume various intensities and tones. The factors that contribute to the natural colour of a diamond are based solely on the diamonds molecular structure except for black coloured diamonds where the inclusions within the diamond are the cause of colour.

Natural fancy coloured diamonds are an extreme rarity and it is important we check each fancy coloured diamond to ensure the diamond is not treated to enhance or change the diamond colour (see colour treatments). Once we have established the diamond is naturally coloured, we can then begin to describe the colour of the diamond.

Describing the colour of a fancy coloured diamond is not the same as describing the colour of “cape series” diamonds using the D-Z scale as found in the 4C’s. It is just as subjective, and there are many ways to describe colours.

First of all the intensity of the colour must be described:

- Fancy Light
- Fancy
- Fancy Intense
- Fancy Vivid

Secondly, the primary colour must be established. Some diamonds will only have a primary colour to describe them (yellow, blue, pink). The final stage in establishing the colour of a fancy coloured diamond is to identify the secondary colour where applicable. Some diamonds, while they are one particular colour, will exhibit a small hint of a secondary colour. For example “Fancy Intense Blue-Green” where blue is the primary colour and green is the secondary colour. You should expect this diamond to be mainly blue with a hint of green.

Clarity is a secondary factor when considering the rarity and value of a natural fancy coloured diamond. While it is graded for clarity as normal (see 4C’s clarity) the colour is the most important feature of these diamonds.

At IGR all fancy coloured diamonds that are graded will be given a special Fancy Coloured Diamond Certificate.