Diamond colours

Natural diamond colours and their rarity

For most people, the word ‘diamond’ evokes the image of a clear, white gemstone. But although the white diamond is favoured by tradition, white is far from the only colour a diamond can have. In fact, natural diamonds come in a wide range of fancy colours – though all natural fancy colour diamonds are rare.

In this entry, you’ll learn about fancy colour diamonds, how they are created, and how rare the different diamond colours are. Below, you’ll also see a selection of the different raw fancy colour diamonds we offer at RoughDiamonds.dk.

How natural fancy colour diamonds come to be

Nature is colourful, and although our familiarity with the white diamond makes it hard to believe, fancy colour diamonds are simply a product of nature.

Natural diamonds form over millions of years through exposure to extreme forces of heat and pressure. These forces affect size, shape, and other factors that determine which type of diamond will emerge once the gemstone completes its journey towards the surface of the earth.

On this journey, sometimes the forces involved can cause distortions in the lattice of carbon atoms which the diamond is made of. And as the diamond travels upwards, certain natural elements – such as nitrogen or boron – can saturate the diamond and alter its microscopic structure. These structural alterations will affect the way the gemstone interacts with light – and this is what gives the diamond its fancy colour.

Fancy colour diamonds and their rarity

In every 10,000 natural diamonds, it is estimated that only one is classed as a fancy colour diamond. This makes all natural fancy colour diamonds rare – but some colours and depths of shade are rarer than others.

The natural colouring of diamonds can vary immensely. Some show only a hint of colour or a patch of cloudiness, while others are far more distinctly coloured. Depending on hue, tone, and saturation, fancy colour diamonds are awarded various grades, including fancy light and fancy through to fancy intense and fancy vivid.

Regardless of their grade, however, what all colour diamonds have in common is their natural beauty. At RoughDiamonds.dk, we celebrate the natural imperfections that give raw diamonds their unique and individual beauty. These elements – including their natural colour variations – are what make raw diamond rings truly special.

Below, you can learn more about the rarest diamond colours and how they are created.


The rarest diamond colours


Pure orange diamonds are the rarest colour diamonds of all. That also means they’re among the most valuable diamonds in the world.

While orange diamonds are rich in nitrogen, the true reason for their vibrant colour remains a bit of a mystery. However, diamond experts generally believe that their colour comes from their being created about 150-200 km below the surface of the earth – deeper in the ground than other rough diamonds.

The pressure and heat present at this depth – two of the most important factors in the creation of diamonds – are greater, which causes a plastic deformation in the atom lattice structure of these diamonds. This makes for diamonds that handle stress exceptionally well.

It also means that their colour might not be even throughout, and sometimes a rough diamond contains only a spot or a hint of colour. To us, however, this is part of their natural beauty – and it only makes them more captivating.

Pink, red, and purple

Like orange diamonds, pink, red, and purple diamonds are formed when their microscopic atomic lattice is distorted by intense heat and pressure. They are all among the rarest diamond colours, but red diamonds are by far the rarest. In fact, they’re so rare that less than 30 true red diamonds are known to exist.

The mine which is most famous for producing natural orange, pink, purple, and red diamonds is the Argyle Mine in Australia. The mine opened in the 1980s and has since gifted us with many incredible jewels. However, mining operations ceased in November 2020, as the life of the mine could no longer be extended.

Despite only 1% of the Argyle Mine production being pink diamonds, the mine still accounts for approximately 95% of all natural pink diamonds on the market.

Other mines have rough pink diamonds (though not always of the same high quality). For example, such mines exist in Russia and in Williamson, Tanzania, where a gorgeous pink diamond known as the Williamson Pink was found and gifted to HM Queen Elizabeth of the United Kingdom in 1947.

The most valuable jewel ever sold at auction is the Pink Star Diamond. One of the world’s great natural treasures, this pink diamond sold for the world record price of US $71.2 million in 2017.


Blue diamonds are very rare. Similarly to grey diamonds, the beautiful colour of the blue diamond is created by the presence of boron in the carbon lattice which makes up the gemstone. The higher the boron levels, the more vibrant the shade of blue.

One of the most famous jewels in the world, the Hope Diamond, is a blue diamond. A fancy dark greyish blue diamond, this jewel has an estimated value of US $200-350 million. Another notable blue diamond is the 16.08 ct. Blue Moon of Josephine: sold for $48,4 million in 2015, this was the most expensive diamond sold at auction that year.

Boron joining the creation party somewhere between 900 million and 3 billion years ago isn’t that common, which makes natural blue diamonds some of the rarest rough diamonds. This also means that we don’t often get to see them. In fact, we’ve only ever had one in our Hidden Boutique in Copenhagen, and we would classify that stone as a whitish blue. This means that we unfortunately can’t promise that we will be able to find a rough blue diamond for you.

Their rarity also means that the price for a natural blue diamond is very, very high, and for most diamond dealers, it is a better investment to have them cut than to sell them to us in their natural form. However, although we might not be able to find a blue-blue rough diamond for you, we might be able to find something on the same colour spectrum or a stone with a blueish tint.


Natural green diamonds are something special. Deep beneath the surface of the earth, the naturally occurring radiation of uranium and other radioactive minerals creates green diamonds. After billions of years, a natural green diamond becomes chemically inert. However, all green diamonds are still tested for radioactivity before we get our hands on them.

Because diamond is the hardest material on earth, the radiation underground cannot penetrate all the way through the diamond. It sits only within the surface level of the stone, which means that if the diamond is cut, it may lose some of its colour and end up a clear, white, colourless stone.

However, its colour can also grow more intense from the heat of the cutting process – or the stone can reveal a different, and perhaps even rarer and more intense colour beneath the surface. This makes green diamonds highly sought after.

Green diamonds almost always yield a great, high quality result when cut, and this affects their price. In the past year alone they have tripled in price, and – depending on their overall quality – they are among the most valuable diamonds in the world.

Of course, at RoughDiamonds.dk we love them simply because they come from Mother Nature – and that includes their quirks and imperfections.


Although diamonds are made of compressed carbon, sometimes other elements will crash the creation party and make the resulting stone much more colourful. Such is the case with nitrogen, which is most commonly found in South Africa. When a diamond is saturated with nitrogen, the fancy colour yellow is created.

Though yellow is one of the more common fancy colours, yellow diamonds are nonetheless extremely beautiful. They come in a variety of shades ranging from pale lemon to vibrant canary yellow.

Light yellow is at the lower end of the GIA (Gemological Institute of America) colour-grading scale. This scale begins with the letter D, representing the colourless white diamond. The scale continues with increasing presence of colour to the letter Z, which represents light yellow or brown.

However, this does not mean that yellow diamonds are not rare or valuable – it all depends on the intensity of colour. In fact, fancy vivid yellow diamonds can be both rarer and more valuable than the whitest D colour diamond. In the end, however, all that really matters is what colour you fall in love with. 


Brown diamonds are among the colour diamonds known to have been used in jewellery in ancient times. They come in colour varieties from rich cognac and deep chocolate to a light brown champagne colour.

Like orange, pink, purple, and red diamonds, they get their colour from the distortion of their atomic lattice by the high pressure and temperature beneath the surface of the earth.


Grey diamonds fall into two categories: fancy grey diamonds and included / salt and pepper grey diamonds.

Like blue diamonds, some fancy grey diamonds are created from being infused with boron. (Some laboratory graded grey diamonds may also have hints of blue within them – this is particularly visible in ultraviolet light such as sunlight.)

Most fancy grey diamonds, however, get their colour due to high concentrations of hydrogen. Like in white, colourless diamonds, high clarity is sought after, and fancy grey diamonds are graded on the same scale as white diamonds.

Included diamonds, also known as salt and pepper diamonds, are diamonds with a high presence of ‘salt’ - white inclusions – and ‘pepper’ – black inclusions. These imperfections give the diamonds a beautiful and unique look, and no two diamonds of this kind will have the same pattern.


A few years ago, black diamonds weren’t considered ‘fine’ diamonds at all – in fact, some even went as far as calling them worthless. In recent years, however, black diamonds have gained popularity for their raw beauty.

Black diamonds get their colour from hematite, ferric iron, or from coal that did not crystallise completely when Mother Nature created them 900 million years ago. Rough black diamonds tend to have a large number of inclusions which are hidden by their colour. This means that when these diamonds are cut, they often crack and lose their colour.

Most cut black diamonds are treated in order to preserve their colour. At RoughDiamonds.dk, however, we love them just the way they are. We would never cut them or treat them with anything – except for love.


Where are the rarest diamonds of color found?

We have gathered all the rarest diamonds ever discovered and placed them in a world map. The map below shows the specific location points where the most expensive diamonds were mined. The African continent is home to some of the top diamond producing nations with most of the world's gem-quality diamonds mined there since the 1870s. Also, India has collected some rare diamonds throughout time with The Koh-i-Noor being the most expensive diamond in the world.


Biggest colorless diamond in the world

A great discovery was made in South Africa back in 1905. The Premier mine in Cullinan, South Africa has a reputation for mining some of the most famous diamonds and also the biggest diamond in the world. The 3,106.75 carat diamond named after its birthplace is the biggest rough diamond ever discovered. It was named after Thomas Cullinan, the mine's chairman. In April 1905, it was put on sale in London, but despite considerable interest, it was still unsold after two years. In 1907, the Transvaal Colony government bought the Cullinan and Prime Minister Louis Botha presented it to Edward VII, King of the United Kingdom, who had it cut by Joseph Asscher & Co. in Amsterdam.


Cullinan produced stones of various cuts and sizes. The largest of which is named Cullinan I or the Great Star of Africa, weighing an incredible 530.4 carats, is the largest clear cut diamond in the world. The stone is mounted in the head of the Sovereign's Sceptre with Cross. The second-largest is Cullinan II or the Second Star of Africa, weighing 317.4 carats, mounted in the Imperial State Crown. Both are part of the Crown Jewels. Seven other major diamonds, weighing a total of 208.29 carats, are privately owned by Elizabeth II, who inherited them from her grandmother, Queen Mary, in 1953. The Queen also owns minor brilliants and a set of unpolished fragments.


Let yourself fall in love with the natural colours of diamonds

Now that you know more about fancy colour diamonds and how they come to be, we hope you feel inspired to go beyond tradition and choose the natural diamond colour that best reflects your personal tastes.

At RoughDiamonds.dk, you can browse our collection of raw diamond rings and see the many beautiful, natural diamond colours set in hand-crafted works of jewellery art. You can also select your very own raw colour diamond and collaborate with designer Maya Bjørnsten and our team of expert goldsmiths to create a bespoke, one-of-a-kind piece.

To keep up with our work, visit our Facebook and Instagram pages and let yourself be inspired by the beauty of fancy colour diamonds in their raw, natural form.