![]() ![]() They like to see well thought-out details for grand projects that already have a solid foundation of prior research. However, although curiosity-driven science produces important breakthroughs, it isn’t normally funded by major funding agencies. So, nature appears to have given us clues on how to make shaped ultra-hard micro machine parts! If we can find a way to replicate the process preserved in the meteorites, we can make these machine parts by replacement of pre-shaped graphite with lonsdaleite.īeing able to study these weird folded diamonds was possible because lead author Andrew Tomkins had time to follow his nose – we call this type of research “curiosity-driven science”. The difference is that we think the lonsdaleite replaced the shaped graphite at moderately higher pressures than those normally used to grow diamonds, from a supercritical fluid rather than a gas. These manufactured diamonds are widely used in industry today, particularly for cutting and grinding because diamond is so hard. The process is quite similar to a process used to manufacture diamonds known as chemical vapour deposition. How rare minerals form when meteorites slam into Earth Then, shortly after, diamond and graphite partially replaced the lonsdaleite as the fluid further decompressed and cooled to form a gas mixture. We think this was driven by the hot fluid mix as pressure and temperature dropped immediately after the cataclysm. ![]() Of course, it’s not actually possible to fold lonsdaleite or diamond – it formed by replacement of pre-existing shapes. This mix then caused lonsdaleite to form by replacement of the folded graphite crystals, almost perfectly preserving the intricate textures of the graphite. Evidence in the meteorites suggested the disruption event produced a rich mix of fluids and gases as it progressed. The second stage happened in the aftermath of the gigantic collision that catastrophically disrupted the ureilite parent asteroid. This exciting discovery could perhaps encourage some Arab countries to better appreciate these finds as real cultural assets and additions to their heritage, rather than taking advantage of them by selling them, as shown by the presence of about 1700 samples of Moroccan stars in foreign museums, spread around the world.Schematic indicating the timing and positions of diamond and lonsdaleite formation as the ureilite parent asteroid was partially destroyed by a giant impact (Ol, olivine Px, pyroxene). Several conditions are required for this transformation, including a temperature rising above no less than 2000°, an atmospheric pressure of at least 30 GPa (GigaPascal) and a sufficiently long collision time (a few seconds) to ensure the formation of diamond.Īll the elements were combined and thus changed NWA 12606 into an even rarer and more precious stone. Several very meticulous analyses were made on the rock before discovering these tiny diamonds, encrusted between different components (of millimetric dimensions!) such as olivine (at 90%), pyroxene (at 5%) or graphite (at 5%).īut how do diamonds end up in the universe? The formation of this gemstone comes in fact from the violent impact of the asteroid which crashes on the Earth, splitting the atmosphere: because of the extremely intense heat and pressure, the solid graphite inside the rock changes into diamond. Ureilites take their name from the Russian village Urey, where a similar meteorite landed in 1886. Its formation is believed to be four billion six hundred million years old, almost the same as the Sun and the planets! Classified in the family of the primitive achondrites, and more particularly in the sub-category of Ureilites, very rare stones which represent 0,6% of all the falls, it has a very particular mineralogical composition. This stone, which was found in 2018 in the Drâa-Tafilalet region, is extremely important for science: indeed, these star fragments are among the only elements that can offer us a glimpse at the History of the Universe. The meteorite had been exhibited in the Agadir Museum for two years, before Moroccan specialists, including Professor Ibhi, and their Italian colleagues decided to carry out a more in-depth analysis. Out of the 120 meteorites of various categories displayed in the museum, this fabulous discovery was made on NWA 12606. ![]()
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