Researchers have discovered an intriguing mineral inside an iron meteorite that fell in Russia two years ago. Although only microscopic crystals were discovered, the researchers were able to estimate some of its properties, including its hardness. The team think that the new mineral could be as hard as diamonds.
The discovery was announced at the 81st Annual Meeting of The Meteoritical Society. The mineral was named "uakitite" after Uakit, the name of the asteroid. Uakitite is made of nitrogen and a transitional metal called vanadium. This is the first example of a vanadium nitride to be found in nature, and it is also the first example of a natural compound made of vanadium and nitrogen that is oxygen free.
“To prove the discovery of a new mineral, it is necessary to obtain data on its crystal structure,” senior author Professor Viktor Grokhovsky, from Ural Federal University (UrFU), said in a statement. “Since the size of uakitite is very small, about 1-5 microns, it was impossible to solve this problem by the traditional method of X-ray analysis. The structure was studied on the equipment of UrFU scientific and educational center 'Nanomaterials and Nanotechnologies' using electron diffraction.”
Electron diffraction is one of the several approaches that use electrons instead of light to study microscopic structures. The crystals inside the meteorite were either in cubic form or little spheres, which depended on the minerals in which they were embedded. The chemical structure was similar to other well-known nitride minerals.
The physical properties of the sample couldn’t be directly obtained since the samples were so small, but by studying the atomic arrangement in the crystal, the team was able to compare it to a synthetic version of vanadium nitride. Vanadium nitride is twice as dense as diamond and it has a hardness on the Mohs scale, between nine and 10. Diamond is the hardest material at a hardness of 10.
Meteorites continue to provide researchers with intriguing tidbits of extreme mineralogy – some had never been seen before, some were only produced in the lab, and others are helping us understand the solar system before the Earth formed.
