When we think of diamonds, many of us conjure up images of brilliant, colourless gems set in stunning engagement rings and dazzling feature-piece necklaces.

Public perception of coloured diamonds

While these imaginings are certainly true, they don’t take into account the myriad coloured diamonds that are out there in the world. Some people have the idea that coloured diamonds are made artificially or have somehow had their pigment manipulated during the formation process. However, the truth is that coloured diamonds are formed in the same way as their colourless cousins – they’re both the result of carbon atoms being forced together in extreme conditions deep beneath the surface of the Earth.

What causes the presence of colour in these diamonds?

If all natural diamonds are created the same way, why do some contain colour? Well, during formation, external particles can enter the crystallisation process. Over time, these foreign bodies can have a significant effect on the chemical process, and over time cause the diamond to develop a unique and distinct colour. Let’s take a look at which factors result in the creation of each colour of diamond.


The undisputed colour of love and romance, pink diamond jewellery is the perfect gift to show that special someone how much they mean to you. It’s thought that pink diamonds are created due to above average levels of intense pressure and heat, which results in a process known as ‘plastic deformation.’ The Argyle mine in western Australia, the largest producer of coloured diamonds in the world, is home to many of these gorgeous stones.


Green diamonds are exceedingly rare. Ranging from a mild tone to a deep verdant, these diamonds obtain their unusual colour from absorbing the radiation that naturally exists in the rocks and soil near the surface of the planet.

– Yellow

Yellow diamond rings are steadily gaining popularity in Hollywood as people come to appreciate the warm, gentle hues of the mesmerising gem. The colouration comes from the presence of nitrogen atoms during the formation process.


Sophisticated and regal, blue diamonds are typically a result of the presence of the chemical boron. The exact tone of blue depends on the boron content of the diamond.


The rarest  – and most expensive – colour of all diamonds is red. The jury is still out on how these unique gemstones are exactly formed, though it’s thought to be a similar process to that involved in the creation of pink diamonds.