Black Diamonds: All You Need to Know

HD021 black rose gold diamond halo engagement ring dublin featureHere at Commins and Co Jewellers, we’ve noticed a sharp increase in the number of inquiries about black diamonds recently. As a result, we’re bringing you all the information you need about this popular engagement ring trend!

Coloured stones have certainly gained popularity with brides-to-be as an alternative to the classic white diamond. However, a black diamond is sure to stand out from the crowd. The dark colour looks fabulous on a solitaire setting or mixed with white diamonds in a glittering halo. This fashion-forward stone is set to become a permanent feature in our ring collection.


Brief History

Now a prized possession among many owners, black diamonds weren’t held with high regard. This was until jewellery designers started using them in their designs in the late twentieth century. As a result,this jewel became a classic example of how putting something in the right packaging will change its value over night.

There were a few famous ones over the years, but the story of the Eye of Brahma black diamond is one to behold.

Legend has it that in the early 1800’s a 67.5ct black Orloff called the Eye of Brahma was stolen from an idol in India. This brought a curse upon many of its unfortunate owners who committed suicide as a result. Eventually it was recut to break the curse.

Black diamonds have become recently famous within pop culture causing them to ‘trend’. Mr. Big adorned Carrie with a black diamond engagement ring in the 2010 ‘Sex and the City’ movie. These days you only need Hollywood on your side and you can increase an item’s value. Other examples in pop culture include both Carmen Elektra & Kat von D who have been seen sporting these mysterious stones.

Who knows how their value will fluctuate in years to come.

HD063 Black Diamond Halo Engagement Ring featureWhat are Black Diamonds?

Found in very rare locations such as Brazil and Central Africa, many people question whether black diamonds are ‘real’. Black diamonds are in fact real, like white diamonds. However, there are three different types that one needs to consider before purchasing.

  1. Natural black diamonds.
  2. Treated black diamonds.
  3. Man-made black diamonds.

All three types are real but there is a huge difference in price and how they are made. So it’s important to research them if you’re planning on buying one.

In comparison to other diamonds, black diamonds are entirely opaque and are incredibly precious. Although they are more affordable, they are still considered quite valuable.


black diamond halo engagement ring hd064 image 2How Black Diamonds Get Their Colour

Research into how black diamonds get their colour is recent but there is no one explanation for the reason. Most black diamonds get their colour from large quantities of minute mineral inclusions. These include graphite, pyrite or hematite but this varies according to the type.

  1. Natural black diamonds: These are quite different to natural coloured diamonds, which get their colour from impurities during the formation process. Black diamonds are more similar to white diamonds that have a high amount of inclusions. Assisted by clusters of graphite inside them which makes them appear black. A natural black diamond is a beautiful stone and has a very distinctive appearance unlike other diamonds on the market. These are the most expensive and rarest form of black diamond.
  2. Treated black diamonds: These are regular white diamonds with high amounts of inclusions which make them low in value. Most black diamond jewellery and engagement rings are in fact treated. This is done through high temperatures and low pressures to induce the colour. These are usually the cheapest variety of black diamonds.
  3. Man-made black diamonds: Most of the black diamonds which are on the market today are man-made. They are usually made in a lab and go through a treatment process to give them their black colour.


Determining the Quality & Value of Black Diamonds

Similar to white diamonds, black diamonds are also graded using the 4 Cs: Cut, Colour, Clarity and Carat weight.

Diamond Cut

Black diamonds have a simpler shape than most white diamonds. This is due to the extreme skill and expertise needed to cut this dense material. The facets will be judged on the smoothness of the surface and how clean the edges are. The surface itself should have a dark, glossy appearance.

Diamond Colour

This category is judged both on the even distribution of colour within the stone and its particular hue. A specialised heat treatment is used to develop the deep tones of the diamond. This results in shades of green or brown so dark they appear black to the naked eye.


Apart from the exceptionally rare ‘Flawless’ diamond, as a natural material all diamonds will contain evidence of their unique growth history in the presence of inclusions. Black diamonds are no exception and their clarity is rated from AAA to I1.


The density of a black diamond is slightly higher than its white equivalent, meaning a black diamond will be a little bit smaller than a white diamond of the same carat weight and shape.