image: (A) This is the original khatyrkite-bearing sample used in the study. The lighter-colored material on the exterior contains a mixture of spinel, augite, and olivine. The dark material consists predominantly of khatyrkite (CuAl2) and cupalite (CuAl) but also includes granules, like the one in (B), with composition Al63Cu24Fe13. The diffraction patterns in Fig. 4 were obtained from the thin region of this granule indicated by the red dashed circle, an area 0.1 mm across. (C) The inverted Fourier transform of the HRTEM image taken from a subregion about 15 nm across displays a homogeneous, quasiperiodically ordered, fivefold symmetric, real space pattern characteristic of quasicrystals. This image relates to an article that appeared in the June 5, 2009, issue of Science, published by AAAS. The study, by Dr. L. Bindi at Universita degli Studi di Firenze in Florence, Italy, and colleagues, was titled, "Natural Quasicrystals." view more
Credit: Image courtesy of <i>Science</i> /AAAS