Phasons in natural quasicrystals.

The discovery of the natural quasicrystals icosahedrite (Al63Cu24Fe13) in 2009 opened a new frontier in mineralogy. The quasicrystals were found in a meteorite formed in the earliest moments of the solar system which means these processes were active 4.5 billion years ago. Using the ID28 side station beam line we propose to fully characterise the structural quality of this natural quasicrystal. In particular we will quantify the eventual amount of phason strain and phason fluctuations by precise measurement of Bragg peak position and width, and the presence of eventual diffuse scattering. The results will be compared to measurements on a single grain quasicrystal grown with the same composition in the laboratory.