Colour is one of the key factors that affects the appearance and value of a diamond. In the UK and worldwide, gemmologists use a colour grading scale from D (colourless) to Z (noticeable yellow or brown) to describe how much colour a diamond has. Understanding this scale helps you choose a stone that balances beauty, budget and personal preference.
### The diamond colour scale
- D‑F (colourless): The rarest and most expensive; diamonds appear icy white with virtually no colour. Best for platinum or white gold settings.
- G‑J (near colourless): Slight traces of colour visible only to trained eyes; excellent value and still look white when mounted.
- K‑M (faint colour): Warm tint becomes noticeable; works well with yellow or rose gold settings where the metal complements the colour.
- N‑R (very light colour): More obvious yellow or brown hue; often used in antique or vintage style jewellery.
- S‑Z (light colour): Pronounced colour; commonly used for fancy colour diamonds (e.g., light champagne).
### How colour affects price and appearance
- Rarity: Colourless diamonds (D‑F) are rare, driving up price. Near‑colourless stones offer a balance between appearance and affordability.
- Setting metal: White metals like platinum or white gold emphasise colourless grades. Yellow or rose gold can mask a faint tint, allowing you to choose a lower grade without sacrificing appearance.
- Size matters: Colour is more apparent in larger stones; consider choosing a slightly higher colour grade for stones over 1 ct.
### Tips for choosing the right colour grade
- Match to metal: Pair lower colour grades (K‑M) with yellow or rose gold to blend the tint; choose higher grades (D‑H) for white metals.
- Prioritise cut and carat: Excellent cut and sparkle can make a slightly lower colour grade appear whiter.
- Compare side‑by‑side: Viewing stones together helps you see subtle colour differences and decide what your eye prefers.
### Frequently asked questions
What colour grade is best for an engagement ring?
Grades G‑H offer excellent value and look nearly colourless in white metal settings. For yellow or rose gold, consider grades I‑K.
Do lab‑grown diamonds have colour grades?
Yes. Lab‑grown diamonds are graded using the same GIA colour scale as natural diamonds.
Is colour or clarity more important?
Colour and clarity both influence a diamond’s appearance and price. For most people, a near‑colourless stone with eye‑clean clarity (no visible inclusions) offers the best value.
Are fancy coloured diamonds graded differently?
Yes. Fancy colour diamonds are graded based on hue, tone and saturation rather than the D‑Z scale.
Last updated: March 2026