What Makes Natural Coloured Diamonds Special? | BNT Diamonds

What makes natural coloured diamonds special?

Natural coloured diamonds are very exclusive and rare, even rarer than colourless diamonds. A true natural coloured diamond has been gifted to us by nature and can be found in a variety of shades, from pink to yellow to brown and even red and are they only found in a handful of places.

Only one in every 10,000 diamonds has a natural colour, which is why these diamonds are called fancy coloured diamonds. These stones are purchased almost exclusively for the intensity and distribution of the colour of the diamond. Criteria considered when purchasing a white or colourless diamond, such as cut proportions and clarity, are less important when purchasing a fancy coloured diamond.


Coloured diamonds come about due to various factors. For instance, yellow diamonds owe their cheerful hue to the presence of nitrogen. Blue diamonds owe their colour to the boron they contain. The cause of pink and red diamonds’ remarkable colour is not certain, although speculations state that they are the result of fractures in the crystal lattice. The rarer the colour and the more intensely the colour shows, the higher the value. Yellow and brown diamonds are most commonly found, while red, blue, and green diamonds are among the rarest of all fancy colours.


Colour intensity, namely the deepness or richness of the colour, is the most important parameter when purchasing a coloured diamond. The more intense the colour, the rarer and more valuable the diamond will be. Diamonds with lighter colour intensity levels such as faint, very light, light, fancy light, and fancy are more common than diamonds with richer intensities like fancy intense, fancy vivid, and fancy deep, and thus less valuable.

All fancy coloured diamonds from BNT Diamonds are 100% natural and not treated.

Below you can find some examples of different colours and intensities:

Fancy pink brown

Fancy pink-brown

Fancy pink brown

Fancy brownish-pink

Fancy light pink

Fancy light pink

Fancy pink

Fancy pink

Fancy deep pink

Fancy deep pink

Fancy brownisch pink

Fancy brownish greenish-yellow

Fancy grayish

Fancy grayish/greenish yellow

Fancy light yellow

Fancy light yellow


After colour grade, carat weight has the biggest impact on the price of fancy coloured diamonds. One carat equals 0.2 grams. The word "carat" comes from the carob seed, the original unit of measurement for diamond traders. The diamond’s price increases with every carat because they become rarer. Fewer than one in one million mined rough diamonds are large enough to produce a polished 1-carat diamond. The diamond prices for fancy coloured diamonds rise exponentially with carat weight.


Natural fancy diamonds are primarily cut to emphasise their colour. This contrasts with colourless diamonds, which are cut to maximise their sparkle or brilliance. While fancy coloured diamonds still exhibit brilliance, colour is the most important characteristic considered when they are being cut.


Shape refers to the overall outline of the diamond when viewed from the top (e.g. round, princess or cushion). A lot of coloured diamonds are cut into non-common shapes to enhance their natural colour. Because of the rarity of fancy coloured diamonds, not all colours are available in all shapes at any given time.

If you are looking for a specific fancy coloured diamond, please contact our experts through info@bntdiamonds.com or +32 3 201 24 90.


Fancy yellow diamonds



As diamonds are formed deep within the earth under extreme heat and pressure, they often contain unique birthmarks, either internal (inclusions) or external (blemishes). Clarity grading goes from LC (loupe clean) or IF (internally flawless) to I3 (included). The higher the clarity scale, the more precious and special the diamond, and the higher the price.
Due to the nature of natural fancy diamonds, clarity is less important than it is in their colourless counterparts because inclusions tend to be masked by the diamond's colour.