Colourless diamonds are the most know, but over the past years coloured diamonds have also gained popularity. Some colour varieties are yellow, pink or red, but what about black diamonds? Are black diamonds always real? How does their colour come about? Uniglo Diamonds shines a light on this beautiful gem.
What causes black diamonds to be black?
Just like colourless diamonds, the black variety forms under extreme pressure and heat. Pure carbon is then transformed into a rough stone, where the atoms are arranged in a crystal structure. A black diamond has a large amount of inclusions, small imperfections, which over time have been coloured black by the presence of graphite, pyrite or hematite.
Unlike yellow diamonds for example, where there are different shades of colour, black diamonds only come in one colour shade: fancy black. However, an intensely dark black diamond is very rare and has an opaque appearance with a high luster. These natural-colour black diamonds are very difficult to work with because of their many inclusions. Using one of these in a jewellery setting has to be done with the utmost care and precision. Most black diamonds used in jewellery have been treated to intensify their colour. Many of those black coloured diamonds were grey to begin with and had many imperfections visible to the naked eye.
4C: Cut, Carat, clarity and Colour
Whilst uncoloured diamonds and most coloured diamonds are usually graded based on the 4C’s, things are slightly different when it comes to black diamonds.
The first C, Cut, is also important for black diamonds, treated or natural. The cut refers to the shape and style in which the diamond is shaped.
The second C, Carat, refers to the weight of the diamond, and not the size like many believe. Black diamonds are more dense than other diamonds which results in a 1 carat black diamond looking smaller than a 1 carat white diamond.
Thirdly, Clarity, indicates the amount of inclusions your diamonds has. Black diamonds usually aren’t graded in the regular way when it comes to clarity, but it remains important that there are no inclusions to be seen with the naked eye.
Lastly the fourth C, colour, cannot be graded according to the standard coloured diamonds scale. Black diamonds will be graded as Fancy black, with the mention of a natural or treated colour.
Are black diamonds expensive?
Whilst black diamonds are scarcer than colourless diamonds, the demand is significantly lower. That’s why black diamonds generally cost less than colourless diamonds.
Famous black diamonds
Black diamonds are less frequently used in jewellery, however they have gained in popularity the past few years. There are more and more celebrities that choose this gemstone as the centerpiece of their special jewellery.
The most famous black diamond engagement ring seen in a movie is probably the one in Sex and The City 2, where Mr. Big gave Carrie Bradshaw a stunning engagement ring with a 5 carat black diamond.
There are three natural black diamonds that are quite famous because of their size and cut.
Firstly, we have the Spirit of Grisogono weighing no less than 312.24 carats, the second largest natural black diamond ever found. This stone is part of the collection of the famous Swiss jeweler Fawaz Gruosi. It’s his company that cut the 587 carat rough stone into the shape it has today. The black diamond is set on a ring containing more than 700 studded diamonds.
The second most famous black diamond is also part of the collection of Fawaz Gruosi: The Gruosi diamond. Originally, the rough stone had a total weight of 300.12 carats and was cut over a period of three years into a heart shaped 115.34 carat black diamond. Today it acts as the centerpiece of a necklace next to 378 white diamonds, 58.77 carats of smaller black diamonds and 14.1 carat of tsavorite garnets.
Lastly, we have The Korloff Noir Diamond, a beautiful 88 carat black diamond owned by the French Korloff jewelers. This diamond has been cut according to the Korloff-cut, containing 57 facets, which benefits the amount of light entering the diamond.
At this point you know all the main points behind a black diamond. Are you looking for a black diamond or any other coloured diamond? Have a look in our wide online inventory. Would you like to know more about colourless diamonds? Visit our education page (LINK TO EDUCATION PAGE) where you can find all there is to know about diamonds.
Are you interested in having a unique jewel with a black diamond? Our team of skilled gemologist and designers can happily assist you to create the jewel of your dreams.