Unprecedentedly structured diamonds have provided scientists with a comprehensive insight into the impact of the Canyon Diablo meteorite, which struck the United States at a time when our ancestors had not yet migrated to the region.
A recently published study in the Proceedings of the National Academy of Sciences reveals the discovery of a completely new type of diamond. While not as aesthetically pleasing as gemstones, these diamonds could lead to remarkable technological applications in the future.
More notably, these are extraterrestrial diamonds extracted from the Canyon Diablo meteorite, which collided with Earth approximately 50,000 years ago in what is now Arizona, USA. At that time, modern humans (Homo sapiens) existed but had not yet migrated to this area, according to archaeological evidence.
A piece of the ancient giant Canyon Diablo meteorite – (Photo: Dave Pape)
“Through the controlled growth of these structures, they can be used to design superhard materials that are also very flexible, as well as having electronic properties that can be tuned from conductive to insulating,” said chemist Christoph Salzmann from University College London (UCL), a constituent college of the University of London.
These meteoric diamonds have been given the name Iondaleite, in honor of the British crystallographer Dame Kathleen Lonsdale.
According to Live Science, scientists initially believed these diamonds to be a form of hexagonal crystalline structure. They could only form under extreme pressure and temperature, which is thought to be related to the impact between the meteorite and Earth.
However, in this new study, scientists discovered that they are not purely hexagonal crystalline structures as expected; they also exhibit the development of another carbon-based material, almost resembling a structure where diamond and graphite intertwine.
The structures formed in a bizarre overlapping pattern, not perfectly homogeneous like conventional diamonds, making them even more valuable and unique.
They possess properties similar to graphene, a material structured as a one-atom-thick sheet of carbon arranged in a hexagonal pattern. Graphene is still under research on Earth and promises numerous applications due to its unique properties—it is as hard as diamond, yet “light as a feather,” transparent, highly conductive, and a million times thinner than human hair.
The discovery of this structural form in meteorites could open an exciting avenue for material technology.