The romance of the black diamond

Jan 16, 2021

I have a beautiful black diamond necklace in the store and as the winter landscape here in Aspen is marked in contrasts of black and white, I thought I might share some thoughts about black diamonds.

Lots of questions arise around these gems. Are black diamonds real, legitimate? Are they natural? Why have they relatively recently appeared on the market? Is a black diamond different from a white diamond? Is a black diamond colored in the same sense as a yellow, or a pink? One thing is certain, black diamonds are becoming ever more popular, more present and thus more expensive. As designers have gravitated toward them, they have taken the world by storm with their dramatic beauty.

There have always been black diamonds among the white ones. The Portuguese in Brazil, named them “Carbonados” in the 18th century. They were not considered particularly beautiful, however, and their popularity languished. RJ Sutton famously wrote in his 1920’s diamond treatise “an ordinary black diamond is not unlike sealing wax.” We have since learned to appreciate the black diamond.

 There are three types of black diamonds. The most expensive and valuable are called Natural Fancy Blacks. These are completely natural and untreated. These diamonds are rare and very expensive, more rare than their colorless counterparts, actually. These diamonds, like colorless ones, tend to be small. They are extremely difficult to cut, which increases the cost. The most famous of the Natural Fancy Blacks is the beautifully set, 67.50ct “Black Orlov” Diamond.

 The next tier of valuable black diamonds is natural diamonds that have been treated with heat. This heat treatment graphitizes the diamond structure and causes a deepening of the dark color. The heat treatment is responsible for the surge in the black diamonds‘ popularity, as it has increased the availability of the black diamonds for jewelry design. Heating has increased the numbers of attractive stones making them accessible and less prohibitively expensive. Most black diamonds on the market have been heated. 

Another form of treatment is ion radiation. This causes the diamonds to achieve a very dark, dark green color that reads as black. It also causes some stones to achieve an orange, red and teal blue color. I never use stones that have been treated in this manner. 

Lastly, there are man-made, synthetic black diamonds. These are not yet very widespread as they are expensive to make. Small, too perfect, and flat color, I do not like synthetics of any kind. Even fabrics!

Natural and treated black diamonds are very real diamonds. Like their colorless counterparts, they were formed deep within the earth under extremely high pressure and temperature on the element of carbon that produces a repeating geometric pattern in the crystal lattice. When carbon is transformed by the earth’s power and there is nothing but carbon present and the pressure is extreme, then the resulting diamond is clear and colorless. When other elements are present or the pressure is variable the diamonds become colored and/or included. 

Black diamonds look black because they have many inclusion of graphite in the crystalline structure. During the diamond’s formation, before the kimberlite deposits reached the earth’s surface, these elements were imbedded into the diamond structure. Minute inclusions or clouds of graphite, magnetite or hematite make a clear diamond appear black.

These forms of carbon also cause black inclusions in colorless diamonds, and are responsible for grey, and opaque white diamonds as well. Gubelin’s Swiss gemological Institute considers Black, grey and white (opaque) to be “fancy colored-diamonds” like their yellow, pink, blue and brown counterparts.

So yes, black diamonds are real, but does the heat treatment destroy their value? That is a matter of opinion. For the most part in the gem trade heat treatment is accepted as permanent and natural. As with sapphires for example a natural “no heat” certification is considered a superior stone. but heat is an accepted part of the gemstone culture. Certainly, the treatment on corundum (sapphire) affects the value, but not dramatically.

In my opinion the heating of diamonds, and other gemstones has given the market many more beautiful stones to reach a wider audience. These are natural stones that are beautiful and magical. Their value is and should be less than untreated stones, but that does not mean that they have no merit or place in the gem trade. All of the stones that I have used in my jewelry have been priced according to their natural OR treated value.

My Black Diamond necklace with its scarab clasp is extremely special because of the large scale of the diamond beads. 11-9mm! They are impossible to find at this scale. There are inconsistencies in the color of the beads and the surface faceting, but I feel these add to the uniqueness and natural beauty of this necklace. The huge beads have a wonderful metallic luster that makes them look so strong and invincible. The Silver shine makes them sparkle like nothing else but a diamond.

The clasp is hand carved in Germany out of natural silver ore and in the form of a scarab, the symbology of eternal renewal. The one soft pearl comes from Australia, a south sea pearl. The necklace is one of extremes...It is black, grey and white; it contains the hardest gemstone on earth and the softest. The absorption of all color is black and the absence of all color is white..these thoughts are held together by the symbol of eternity renewal. To me, like our world, black and white flow in this necklace in an eternal circle of Beauty and Grace and Unity.