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The ‘Secret’ of black diamonds

Do you want to know a secret?

The world’s most famous black diamonds are those which adorned the Fantasy Bra worn by Adriana Lima at the 2008 Victoria’s Secret fashion show.

Okay, that’s no secret.

But it’s perfectly fitting, since black-diamonds possess a secret of their own, to be revealed below.

Celebrity sightings

Adriana’s “Black Diamond Fantasy Miracle Bra” contained 3,575 black diamonds and 120 colorless diamonds of one carat. Various other gems, including ruby accents brought its total gemstone count to 3,900. The largest, by far, were two black diamond drops weighing approximately 50 carats apiece. The bra was studded with 1,500 carats in total and had an estimated value of $5,000,000.

Ten years later black-diamonds returned to the spotlight when Lady Gaga appeared at the 2018 Grammy awards adorned with 300 carats of Lorraine Schwartz blackened gold and black-diamond earrings and rings.

black diamonds worn by famous celebrities
Photo credit:

So, what is the “secret” of black diamonds?

Drum roll please…

Here it is…

We don’t know how they formed – or where they came from.

It’s true. Black-diamonds, also known as carbonado, stand apart. They have more porosity than other diamonds. Moreover, black-diamonds come from different origins. They are found in alluvial deposits in Brazil and Central Africa. Neither of those places are associated with kimberlite, the usual source of gem diamonds.

Simply put: How and where black diamonds came about is still a secret in the gem world.

Best guess

A paper was published in the December 2006 edition of Astrophysical Journal Letters reporting the discovery of hydrogen trace elements in carbonado black diamonds. The details of that discovery imply that carbonado existed long before the Earth was born, arriving here from interstellar space.

Further speculation suggests that black diamonds may have been the product of supernova explosion. They started as diamonds the size of asteroids first, around a kilometer or more in diameter, and broke up while making Earthfall in the two countries where they are found today.

Apart from the notoriety of some famous (and infamous) black diamonds throughout history, carbonado received relatively little attention from jewelry professionals prior to the year 2000. Mostly fragmentary, black-diamonds traded at low prices and were primarily used in industry.

carbonado also known as black diamonds

Rising stars

In the late 1990s black diamonds made some appearances at key jewelry expositions and started attracting attention. At a Taiwan show in 1998 Mauboussin displayed a black-diamond keychain weighing 64.3 carats and launched a new series of black diamond watches under their brand name.

The trend gained momentum. Many fashion brands began launching black diamonds in jewelry. The movement was crowned in 2008 with the appearance of that famous Victoria’s Secret’s carbonado Fantasy Bra.

black diamond jewelry pieces
Jewelry by Cartier, Oeelin and De Grisogono

Secret society

The good news is that today you don’t need to seek a runway or red-carpet to find these beautiful, mysterious gemstones. Black-diamond jewelry is sold by hundreds of retailers.

And now you know the story.

All of you who own black-diamonds may consider yourselves part of an exclusive society, sharing a mysterious secret. A secret which may reach back to the dawn of time.

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