Black diamond: what you need to know before buying.
Unique, captivating and mysteriously symbolic, the black diamond has gained popularity in the jewellery universe and appears as a bold alternative to traditional colourless diamonds for engagement rings.
How about knowing a little more about this stone that is capable of creating peculiar and fascinating jewellery?
- A brief history of the black diamond
Appreciated and known as “Fancy Black”, black diamonds were once despised. According to JR Sutton's 1928 book "Diamond: The Descriptive Treatise", opinions about the common black diamond being considered a gemstone are divergent.
What is known in fact is that this stone was purchased by jeweller Charles F. Winson and was split into 3 smaller stones in order to rid him of the curse. The stone, now known as Black Orlov, was transformed into a brooch with 107 more diamonds and later into a necklace, which was purchased by Dennis Petimezas in 1995.
Black Diamond Orlov – Photo: GIA
Another famous black diamond that caught attention during the 1990s was the Spirit of De Grisogno , with its 312.24 carats. It is the largest cut black diamond in the world. It was found weighing 587 carats in Central Africa. It was later cut by the Swiss jeweller De Grisogono, known for being a specialist in black diamonds. Today, the diamond is set in a ring made of white gold, alongside 702 other diamonds.
Black Diamond Spirit of de Grisogono – Photo: Gem Rock
Generally speaking, there has always been little interest in black diamonds until, in the mid-20th century, some designers began inserting black stones, along with colourless diamonds, into pieces to create a contrast of colours.
In the last decade, the unique beauty of black diamonds has started to catch the attention of buyers in the jewellery market.
- What are the characteristics of a black diamond?
Many people question whether black diamonds are “real”. It is possible to find a wide variety of diamond colours in addition to the famous and much desired colourless diamonds. Like the pink or yellow diamond, the black diamond is, in fact, a diamond. That is, it is composed of pure carbon, just like a colourless diamond.
However, black diamond has unique characteristics when compared to other types of diamonds.
COLOUR
The black diamond is actually a diamond with numerous inclusions and fractures inside. Because of this characteristic, it has a dark tone. These inclusions are usually composed of small pieces of graphite, pyrite and hematite. The higher the concentration of these inclusions, the darker the diamond.
The colour of a black diamond can vary subtly within a spectrum that goes just beyond black. A natural, untreated black diamond can vary in colour from an almost translucent grey to an olive green or dark brown.
Inclusions and fissures inside the black diamond- Photo: IIJA
WEIGHT
A black diamond is slightly denser than a colourless diamond. This means that if a black diamond and a colourless diamond of identical sizes and shapes are compared, the black diamond will have a greater carat weight than the colourless diamond.
CLARITY
Black diamonds usually have numerous inclusions. This characteristic is responsible for producing the black colour in the diamond. However, there are some black diamonds that have a lower and irregular concentration of inclusions, with a less opaque surface. By exhibiting a certain degree of transparency, it is possible to clearly see the internal features, such as fractures and inclusions of this type of diamond. This characteristic can be seen as a good or a bad thing. It all depends on personal taste.
CUT
Generally, black diamonds are cut simpler, that is, with fewer facets, than most colourless diamonds are. This is because of two factors.
The first is that black diamonds have many fracture points inside, which makes cutting a more delicate and laborious process. Because it is a dense and opaque material, identifying the cleavage points requires a lot of skill and expertise on the part of the cutter. Therefore, the more simplified the cut, the lower the risk of damage to the jeweller.
The second factor is that because it is black and opaque, this type of diamond does not require a more complex cut, which enhances the stone's brilliance, such as a brilliant cut, for example. This type of cut does not make sense in a stone that does not allow light to pass through it.
Cut black diamonds usually have imperfections and irregularities on their surface due to the numerous fractures inside. While these characteristics are not common in colourless diamonds, they are completely acceptable for black diamonds.
Generally, a good cut for black diamonds gives the stone a shiny, mirror-like surface, although the interior remains opaque.
- Types of black diamond
NATURAL
These diamonds acquire a natural dark hue during their formation process. These diamonds have many inclusions and fissures, which tend to make them more opaque compared to a regular diamond. Generally, a natural black diamond has a distinct beauty, so it is rarer compared to other black diamonds on the market. For this reason, this category usually has a higher price per carat; however, they are usually more affordable than a colourless diamond.
It is common to find numerous fractures, inclusions and visible marks on the surface of a natural black diamond. Photo: John I. Koivula / GIA
TREATIES
Most black diamonds available in the jewellery market undergo colour treatment. In fact, many of these diamonds initially have a greyish, brown or olive hue. These stones are subjected to a high temperature and low-pressure treatment, which “graphitises” the fractures, turning them black. Artificial irradiation of colourless diamonds can also produce a green so dark that the diamond appears black.
Typically, artificially irradiated black diamonds show a dark green color when examined under intense lighting. Photo: Robert E. Kane / GIA
CARBONADO
Many people believe that carbonado and black diamond are synonymous. However, while a carbonado is indeed a type of diamond, it is unlikely to be used as a gem in jewelry. In reality, carbonado is a grouping of several diamonds that form a porous, glassy rock, similar to molten glass.
Discovered in Brazil in 1841, it was baptised as carbonado for its appearance similar to that of coal. The origin of carbonado is uncertain. Most diamonds are found in structures called kimberlites. Carbonates are found exclusively in alluvial deposits in Brazil and the Central African Republic. There are several theories about the formation of this type of diamond with such a peculiar structure, and one of them is that it would come from space through an asteroid or even the result of a supernova explosion.
- Determining the value of a black diamond
Black diamonds have an advantage over traditional diamonds: they are usually cheaper than diamonds of other shades.
Colorless diamonds are generally classified according to the GIA method of the 4 C's, using the four criteria: Color – Color , Carat – Weight , Clarity – Clarity and Cut – Cut . And this classification is responsible for determining the value of a colourless diamond.
However, it is not possible to classify black diamonds using the same criteria, after all, they are opaque and, in most cases, have many inclusions. Therefore, they cannot be graded on the GIA clarity scale used for other diamonds. As they are black, there is not an extensive colour variation, and, consequently, there is no classification of shades as in the case of colourless, pink and yellow diamonds. As such, the GIA does not issue grading reports for black diamonds. This type of diamond is classified as natural or treated only.
Generally, natural black diamonds have a higher price per carat compared to diamonds that receive colour treatment.
5. Black diamond care
Black diamonds require the same care as a colourless diamond. However, as it has more fractures and inclusions in its interior than other types of diamond, it calls for extra attention in its use. While every diamond is prized for its superior hardness, these multiple fractures and inclusions, which are responsible for the black diamond's beauty, make it more vulnerable.
One of the important recommendations to prevent damage to your black diamond piece is to keep it away from sources of excessive heat and steam. In addition, ultrasonic cleaning is also not recommended for this type of stone.
6. Engagement Rings with Black Diamond
In the last scene of the movie Sex and the City 2, Mr. Big gives main character Carrie Brandshaw an engagement ring with a 5 carat black diamond. But why a black diamond? He said to her:
"Because you're not like the rest of the world."
Undoubtedly, an engagement ring with a black diamond has a peculiar beauty and carries a strong symbolism. If you've looked everywhere but haven't found any jewellery that represents how special she is, maybe this is the perfect way to surprise her.
Raphana Blackhawk Halo Engagement Ring
