A quick guide to diamond colour types
When you close your eyes and think of diamonds in diamond rings, you probably imagine a crystal, colourless stone that light plays off effortlessly. And the ideal diamond is just that – completely colourless. But, while this is the ideal, it’s often not the reality.
The colour grading scale
Diamonds are classed on a scale from D to Z. D-rated diamonds are those totally colourless pieces of perfection in your mind, while Z-rated diamonds are lightly tinted, and usually come in the form of brown and yellow diamonds. The sub-categories in this rating system are:
D-F: Colourless
G-J: Near colourless
K-M: Slightly tinted
N-R: Very light colour
S-Z: Light colour
This change in colour is extremely subtle, and between letters it is essentially imperceptible to the naked eye. If someone tells you that they can see the difference between a D and an E-rated diamond, they’re probably lying to you. This means that any diamond with a rating above K can usually be used for high-priced jewellery, although the cut and shape of the diamond will have more and more of an effect on clarity the further away from D you go.
When colour is a benefit
The naked eye will start to pick up on colour at around the N-rating onwards. Beyond the S-rating, the colour of the diamond begins to become easily perceptible. Because the Z-rating is still considered a ‘light’ colouring, a new category is opened up to diamonds that fall beyond this point. These are called ‘fancy colour’ diamonds, and can often fetch a far higher price than their pure cousins. The deep blue, green, or pink diamond rings that you see these fancy stones displayed on are highly prized.
Because a yellow or brown tint is the most common coloured imperfection, and because these diamonds can appear to be dirty rather than colourful, these diamonds are less sought after and generally fetch lower prices.
Colour becomes less obvious when set in a piece of jewellery, as the surrounding metal and material will offset the natural discolouration of the stone itself. This means that a K-rated diamond can look identical to a D-rated diamond when set.
