Natural Quasicrystals

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Quasicrystals are solids whose atomic arrangements have symmetries forbidden for periodic crystals, including configurations with five-fold symmetry. All examples identified to date have been synthesized in the laboratory under controlled conditions. Here we present evidence of a naturally-occurring icosahedral quasicrystal that includes six distinct five-fold symmetry axes. The mineral, an alloy of aluminum, copper and iron, occurs as micron-sized grains associated with crystalline khatyrkite and cupalite in samples from the Koryak mountains in Russia. The results demonstrate that quasicrystals can form and remain stable under geologic conditions.

Press: 
“Exotic Quasicrystal May Represent New Type of Mineral,” Scientific American  (Jun 2009)
“Ecco il quasicristallo che nasce in natura,” Corriere della Sera [Italy]  (Jun 2009)

Peter J. Lu  |  Harvard University  |  Cambridge, MA 02138 USA |  plu_at_fas.harvard.edu