¹Paul D. Asimow, ²Chaney Lin, ^3,4Luca Bindi, ¹Chi Ma, ^5,6Oliver Tschauner, ⁷Lincoln S. Hollister,⁸Paul J. Steinhardt
Proceedings of the National Academy of Sciences 113 7077–7081 Link to Article [doi: 10.1073/pnas.1600321113]
¹Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125;
²Department of Physics, Princeton University, Princeton, NJ 08544;
³Dipartimento di Scienze della Terra, Università degli Studi di Firenze, I-50121 Firenze, Italy;
⁴Consiglio Nazionale delle Ricerche–Istituto di Geoscienze e Georisorse, Sezione di Firenze, I-50121 Firenze, Italy;
⁵Department of Geoscience, University of Nevada, Las Vegas, NV 89154;
⁶High Pressure Science and Engineering Center, University of Nevada, Las Vegas, NV 89154;
⁷Department of Geosciences, Princeton University, Princeton, NJ 08544;
⁸Princeton Center for Theoretical Science, Princeton University, Princeton, NJ 08544

We designed a plate impact shock recovery experiment to simulate the starting materials and shock conditions associated with the only known natural quasicrystals, in the Khatyrka meteorite. At the boundaries among CuAl5, (Mg0.75Fe2+0.25)2SiO4 olivine, and the stainless steel chamber walls, the recovered specimen contains numerous micron-scale grains of a quasicrystalline phase displaying face-centered icosahedral symmetry and low phason strain. The compositional range of the icosahedral phase is Al68–73Fe11–16Cu10–12Cr1–4Ni1–2 and extends toward higher Al/(Cu+Fe) and Fe/Cu ratios than those reported for natural icosahedrite or for any previously known synthetic quasicrystal in the Al-Cu-Fe system. The shock-induced synthesis demonstrated in this experiment reinforces the evidence that natural quasicrystals formed during a shock event but leaves open the question of whether this synthesis pathway is attributable to the expanded thermodynamic stability range of the quasicrystalline phase at high pressure, to a favorable kinetic pathway that exists under shock conditions, or to both thermodynamic and kinetic factors.