A legendary carbonado is going to be auctioned at Sotheby’s and online bids are expected to reach several million euros. There has been good reason to believe for more than a decade that this kind of diamond was not born in the Earth’s mantle, at moderate pressures and temperatures, but in a much more exotic environment.
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If you have several hundreds of millions of euros in Bitcoin Where Ethereum and space fascinates you, then an upcoming Sotheby’s Dubai online auction is probably for you, starting February 3. The famous American multinational of British origin of auction of works of art and objects of collection, based in New York, will indeed propose a carbonado and not just any since it is “The Enigma”.
Carbonados quesaco? As Futura had explained for almost 15 years in the previous article below, these are intriguing black diamonds that are only found in certain regions on Earth and which, to say the least, do not seem to have the same origin as the common diamonds found associated with the famous lavas called kimberlites.
“The Enigma” is a spectacular example of this, to the point of having been included in the Guinness Book of Records as the greatest diamond carved out of the world. It has 55 facets and weighs 555.5 carats.
It can also be purchased with more traditional means than cryptocurrencies ; in the meantime, it is exhibited in Dubai until January 20 before taking a tour of Los Angeles and then London.
A presentation of “The Enigma”. © Sotheby’s
Several theories have been proposed to explain the origin of the carbonados, as explained in the video below but for more than a decade, it seems clear that we must admit that they have an interstellar origin and that they are older than the Earth and the Sun themselves.
An interstellar forge?
Indeed, the combination of the composition of carbonados and knowledge of the thermochemical processes capable of producing them strongly suggest that matter carbon in a cloud molecular and dusty interstellar being compressed and heated by the shock wave of a supernova explosion.
The carbonados would then have found themselves incorporated into the matter of the oldest meteorites formed in the protoplanetary disc from Solar system. It is interesting in this respect to remember that there are reasons to think that thecollapse of the cloud at the origin of this disc and of the young Sun was precisely caused by a little bang Of this genre.
A video about carbonados. To obtain a fairly accurate French translation, click on the white rectangle at the bottom right. The English subtitles should then appear. Then click on the nut to the right of the rectangle, then on “Subtitles” and finally on “Translate automatically”. Choose “French”. © SciShow
Black diamond: an extraterrestrial origin
Article of Laurent Sacco published on 01/30/2007
One of the most fascinating enigmas, on the border of geology and astrophysics, may have just found its solution. Black diamonds are of extraterrestrial origin according to a group of researchers in the United States.
As surprising as it may seem, there is indeed a variety of black diamonds found only in Brazil and the Central African Republic in particular geological formations. Also called “Carbonado” since the middle of the 18and century, according to a Portuguese expression meaning “burnt, charred”, they are aptly named because their appearance is that of a piece of coal of drink varying from gray to black, sometimes with porosities.
They are not simply characterized by their color and their geographical location, they also represent a anomaly for mineralogists. Around the world, diamonds are normally associated with volcanic rocks, called kimberlites, generated by violent eruptions bringing diamonds back from areas deeper than 150 km inside the Earth. You should know, in fact, that you need pressures and significant temperatures to cause the generation of diamonds from the carbon.
However, not a single black diamond has ever been found in a kimberlite! Things got worse when it was realized that, on the one hand, they were not a single crystal but an association of crystals and, on the other hand, the isotopic measurements of the carbon 12 to carbon 13 ratio did not correspond to those associated with other diamonds!
In 1985, Joseph Smith of the University of Chicago and J. Barry Dawson of the University of Sheffield in England then proposed that they resulted from the impact of giant meteorites in the Precambrian era. The geological formations where the source of the black diamonds can be found date back more than two billion years, perhaps even four according to certain recent dates, precisely when the meteorite bombardment was intense. However, each time no impact crater could be found.
In the mid 90’s, Stephen Haggerty, which we will soon find again, then enters the scene. He simply proposes that black diamonds do not result from a meteorite impact, but form directly in interstellar clouds, rich in carbon and hydrogen, under the action of the terrible shock waves of the supernovae. The high pressures and temperatures would then be sufficient to create veritable aggregates of black diamonds, the size of an asteroid, which would later be fragmented and fall on the primitive Earth.
How can these hypotheses be made more credible? Simply by measuring the presence ofatoms hydrogen andnitrogen and that’s what Stephen Haggerty and Jozsef Garai of Florida International University have just done with their colleagues Sandeep Rekhi and Mark Chance of Case Western Reserve University. In an article published in Astrophysical Journal Lettersthey relate the various results of their measurements carried out in infrared using the Synchrotron of the Brookhaven National Laboratory.
The “Carbonado” now share many similarities with the micro-diamonds already isolated in meteorites, they are indeed extraterrestrial diamonds!
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