Although it is generally thought that diamonds are colourless, there are actually a wide range of hues which can greatly affect value. Colourless or near-colourless diamonds can be graded. Diamond colours are generally graded on an alphabetic scale, from D, which is the best, to Z, which is a distinctly yellowish-brown colour. However, if a diamond has a strong colour it is termed a fancy coloured diamond and some such stones are much sought after.
This is how we grade the colour of a diamond:
Please see the chart below; you will see the definite change from white at the top of the scale to a faint yellow at the lower end of the scale.
Yellow or brown colour diamonds having colour more intense than “M”, as well as diamonds exhibiting colour other than yellow or brown are considered fancy coloured diamonds. These diamonds are graded using separate systems which indicate the characteristics of the colour, and not just its presence. These colour grading systems are more similar to those used for other coloured gemstones, such as ruby, sapphire, or emerald, than they are to the system used for white diamonds.