Colour

Generally speaking, the closer a diamond is to having no colour, the more valuable it is. This is to exclude the "Fancy" colours such as Red, Green and Blue which are beyond the scope of this article, perhaps a later one if we can persuade an expert to write one for us.

Totally colourless diamonds are extremely rare and expensive. Diamond graders have established various methods of sorting them by colour, no one system is better than another, but the most commonly used today is the GIA system which uses the alphabet from D to Z (no A, B or C) to grade from the whitest to the darkest. Most Commercial stones tend to be in the area between E and R, rarely do you find a D and seldom will you see a S+.

Here is an illustration of how the GIA grading system works.