Researchers had long been amazed by lonsdaleite, meaning hexagonal diamonds. Now they may finally know the origin behind their existence: a dwarf planet colliding with a big asteroid at a time when our Solar System was only beginning to form – 4.5 billion years ago, to be more precise.
The news is brought by space.com. The reason why lonsdaleite is called hexagonal diamonds is simple: the carbon atoms that exist in these gems are arranged in a hexagonal shape. Otherwise, the carbon atoms from normal diamonds are arranged in cubic shapes. Diamonds represent the only gem made of a single chemical element. Being made of 99.95% of carbon, diamonds also have very small amounts of trace elements.
Lonsdaleite found in a rare class of meteorites
According to the new study, lonsdaleite was found in a rare class of meteorites known as ureilite, and they are now believed to have their origin in a dwarf planet.
Dougal McCulloch from the RMIT University in Australia, explained as space.com quotes:
There’s strong evidence that there’s a newly discovered formation process for the lonsdaleite and regular diamond, which is like a supercritical chemical vapor deposition process that has taken place in these space rocks, probably in the dwarf planet shortly after a catastrophic collision,
Chemical vapor deposition is one of the ways that people make diamonds in the lab, essentially by growing them in a specialized chamber.
While the Solar System is about 4.57 billion years old, our planet is calculated to have formed 4.54 billion years ago. The Milky Way galaxy, on the other hand, is 13.61 billion years old. Surely anybody feels a lot younger than they are after reading these numbers!
The term ‘lonsdaleite’ comes from the British crystallographer Dame Kathleen Lonsdale, who was the one who first discovered the gems back in the ’60s.
The new research was published in the Proceedings of the National Academy of Sciences.