Diamond Education


Natural Vs Treated Colour Diamonds

Natural Fancy Colour Diamonds


Natural fancy colour diamonds are formed in the earth under immense pressure and heat, and their colour is a result of natural processes. The colour can be caused by a very small number of defects or impurities. (Yellow and brown diamonds are very common in nature; however, almost all colours are represented in diamonds. Coloured diamonds get their hues like blue, yellow, green, purple, pink, orange, or red due to tiny amounts of impurities, such as nitrogen, boron, hydrogen, or radiation exposure. These impurities cause the diamond to absorb certain wavelengths of light and reflect others, resulting in the unique colour making these naturally occurring diamonds incredibly rare and valuable. However, you can get also get coloured diamonds that been treated to achieve these colours.

Fancy colour diamonds value increases as the intensity and purity of the colour shows. Large vivid fancy colour diamonds are exceptionally rare and extremely valuable. Nevertheless, some fancy diamond colours can be rather more muted than pure and strong.


Calico - Gia Colour Wheel Hue Chart


Treated Fancy Colour Diamonds

Besides naturally coloured diamonds, we have create various processes of treating diamonds to create fancy coloured diamonds. Treated fancy coloured diamonds are diamonds that have undergone a treatment to enhance their colour. These treatments may include irradiation, coating, and HPHT (high pressure, high temperature) treatments. The treatments are used to create fancy colours such as yellow, blue, green and pink.

There are a variety of colours that diamonds can have. The Irradiated diamonds that are yellow, orange, green, blue and pink shades are free of residual radioactivity. After irradiation, the resulting fancy colour is steady and will not fade.

Black coloured treated diamonds are obtained by a graphitization process.

The High Pressure, High Temperature (HPHT) processed diamonds, no irradiation, generate colours, such as pink, blue, and a large range of yellow, lime, orange and brown hues, and produce colours that are unlikely to fade.

The Differences Between Natural Fancy Coloured Diamonds Vs Treated Fancy Coloured Diamonds?

The main difference between natural and treated fancy coloured diamonds is the origin of their colour. Natural fancy colour diamonds are formed in the earth's crust over millions of years, while treated fancy colour diamonds are created by subjecting natural diamonds to high pressure and temperature or irradiation to enhance their colour. Coloured diamonds can be created from lab diamonds, but those will be noted on the diamond certificate. There are however, pros and con’s to choosing each.

Pro’s & Con of Colour Enhanced Diamonds

Affordable: Treated fancy colour diamonds are generally much less expensive than naturally occurring fancy colour diamonds. Treated diamonds can be a great option for people who want the look of a fancy colour diamond but have a limited budget.

More Colour Options: With treated fancy colour diamonds, you have access to a wider range of colours than you might with natural fancy colour diamonds. This is because diamond treatment techniques can enhance or change the colour of the diamond, giving you more options to choose from.

Customization: Diamond treatments can be customized to achieve specific colours or effects. This means that buyers can work with a jeweller to create a unique and personalized diamond that meets their exact preferences and specifications. This level of customization may be difficult or impossible to achieve with natural fancy colour diamonds.
Durability: Natural fancy colour diamonds are more durable and retain their colour better over time, while treated fancy colour diamonds may lose their colour or become discoloured. Therefore, treated fancy colour diamonds are also more likely to be damaged by heat, chemicals, and other environmental factors thus requiring more maintenance and require more careful handling.

Value: Treated fancy colour diamonds will generally have a lower value compared to natural fancy colour diamonds. This is mainly due to the fact the naturally occurring colour diamonds unique origin, extreme rarity, and durability. In the diamond market, natural fancy colour diamonds command higher prices and are considered more desirable.

Rarity: Treated fancy colour diamonds are less rare than natural fancy colour diamonds, which may be a drawback for some buyers. Some people may prefer the exclusivity and rarity of a natural fancy colour diamond, even if it comes at a higher cost.