How are Fancy Coloured Diamonds Formed?

Diamonds are the most precious & sought after gemstones in the world.

Coloured diamonds can be formed naturally and artificially in laboratories - it just takes the slightest change in its chemical balance. Diamonds are one of the most precious and sought after gemstones in the world. Also known as fancy coloured diamonds, a natural coloured is extremely rare and unique. There are 27 hues of natural coloured diamonds, which are all graded using the fancy colour grading scale. The hue, tone and saturation all contribute to the diamonds quality. According to GIA only 1 in 10,000 diamonds are classed as a fancy colour diamond.

The shift in buying habits towards coloured diamonds and personalised pieces has contributed to the increase in demand for fancy coloured diamonds. Due to their rarity,  laboratories are attempting to mimic the tricks of nature in order to capitalise on the growing trend. This trend highlights the importance of knowing how your diamonds are sourced.

How Are Fancy Coloured Diamonds Made?

Diamonds were formed over 3 billion years ago, deep within the Earth's mantle (the layer between the crust and the planets core). Under conditions of intense heat and pressure, atoms crystallise in order to form diamonds. Through volcanic eruptions, these diamonds are   brought to the top of the Earth's surface ready to be mined.

Coloured Diamonds are formed in the same fashion but with a unique difference. When foreign particles are trapped during the crystallisation process, this alters the chemical process. This results in exceptionally beautiful coloured diamonds being created.

Mineral Curator at The Natural History Museum, Mike Rumsey states that,  "perfectly formed diamonds composed only of the element carbon, with no chemical impurities, no internal defects and no extra particles would be completely colourless. But nature rarely produces perfect objects. In the case of diamonds, it is these imperfections that cause colour."

Here are how some of the fancy coloured diamonds are formed:

Red Diamonds

Red diamonds are extraordinarily rare and the most expensive of fancy colour diamonds. Unlike other fancy colour diamonds, red diamonds contain zero impurities - they're pure carbon. Red shades are created through the changes in electron structure during the diamonds voyage to the surface. The rare deformation in its atomic structure is known as plastic deformation. Light passes through the irregular lattice, causing the diamond to reflect a red colour.

Red diamonds are only found and mined in a small number of countries; including Africa, Australia and Brazil. There is only  a handful of unmodified red diamonds available on the market, with the majority of them weighing less than 1 carat. It is predicted that with the rarity of the diamond, prices will continue to increase overtime. Only a handful of red diamonds larger than five carats has been found.

Yellow Diamonds

Yellow Diamonds are formed through the inclusion of nitrogen during the forming process. Nitrogen molecules absorb blue light which allows the diamond to reflect as yellow.

Yellow diamonds are the most common coloured diamonds formed, making up 60% of coloured diamonds in the world. The most vivid yellow diamonds however are only found and mined in South Africa, thus making them quite rare.

Adored by the rich and famous, yellow diamonds are continuing to increase in popularity. Yellow diamonds are perfect for giving a modern twist to any piece of jewellery. Most commonly used to add a unique pop of colour to engagement rings.

Black Diamonds

Black Diamonds are formed through the impurities attached to them during the formation process. The high levels of inclusions and clusters of graphite make the diamond appear black in colour.

The uniqueness of black diamonds makes them an extremely special gemstone to have set  into your engagement ring or showcased in a beautiful pendant.

Are Fancy Coloured Diamonds More Expensive than Colourless?

Whether fancy coloured diamonds are more expensive than colourless diamonds is neither a yes or no answer. The price will vary depending on the colour and quality of the diamond. Any unique diamond that is rare and difficult to obtain will be expensive.

Currently the colour of the diamond has a huge impact of the price, due to trends and desirability.

Price range

All diamonds are then evaluated using the fancy colour grading scale to determine a fair price. It is important that you get expert advice when purchasing a fancy coloured diamonds. These diamonds are becoming more sought after and remain rare; many artificial gems flood the market. At Diamond Heaven we only sell natural high quality diamonds that are ethically sourced.

Used in engagement rings, earrings and pendants - a piece of diamond jewellery undoubtedly makes a well treasured gift. When searching for the perfect diamond, referring to the 4 Cs, the diamonds we know best are the most colourless flawless gemstones. At Diamond Heaven we are dedicated in helping you find beautiful diamond jewellery, perfect for any occasion. Whether it is to give to a loved one, or a gift for yourself. Discover our unique and beautiful collection of yellow and black diamond rings.

For advice and support on picking the perfect gift - book an appointment at one of our branches, or contact us on 0121 200 1300.