Understanding Diamond Colour
Diamonds come in wide range of colours, some of them extremely rare (yellows, pinks and blues). In a white diamonds, colour refers to a diamonds lack of colour. The presence of a yellow tint will lower the price of a diamond. The less colour a white diamond has the higher the colour grade and thus the greater its value.
Colour grade is assigned by viewing the diamond in an environment designed to eliminate colour from surrounding surfaces as well as the light source itself. Minor colour differences detected in this environment are very difficult if not impossible to detect in a normal environment. The diamond industry has adopted a colour scale which almost every diamond sold today is rated against.
White diamonds are graded on a scale of D (Colourless) through to Z (Light Colour). All D-Z colour diamonds are considered white, even though they contain a varying degree of colour. True fancy coloured diamonds (yellows, pinks and blues) are graded on a separate colour scale.
Understanding Colour Grades
D – F
There are differences between D, E and F coloured diamonds, they can be detected by a gemmologist in side by side comparisons and very rarely by the untrained eye. D – F colour diamonds are usually set in white gold or platinum. Yellow gold reflects colour and negates the diamonds colourless effect.
G – J
G – J coloured diamonds contain a small trace of colour. This colour is rarely detected by the untrained eye. These diamonds are suitable for a platinum or white gold setting as this would delude the eye of any hint of colour in a diamond.
K coloured diamonds, colour (usually a yellow tint) is more easily detectable by the naked eye. Set in yellow gold, these warm coloured diamonds appeal to many.
Very Light Colour
Diamonds in the N – R colour range have an easily detectable yellow or brownish tint, but they are much less expensive than higher grade diamonds.
S – Z
For almost all customers S – Z colour diamonds have too much colour for a white diamond. Colour is very easily noticeable to the untrained eye.
Colour becomes much harder to detect once a stone is set in a piece of jewellery and hereby placed in an environment that contains colour (as opposed to an all white background used to grade diamond colour). For instance a H colour diamond may look as colourless as a D coloured diamond when set in a ring under normal lighting, especially if the two aren’t compared side by side.
Another key factor that affects a diamonds apparent colour is the colour of the mounting itself. Yellow gold makes slight amounts of yellow less obvious in the diamond, while white metal mounts make the colour in yellow diamonds more apparent.
The vast majority of untrained observers (and many gemmologists) cannot place an exact colour grade on mounted jewellery and this is why in the industry a group grade or range of grades is given if diamonds are graded subsequent to being set.
Colour becomes more important as carat weight increases, this is simply because colour is easier to perceive in a larger diamond.