Icosahedrite

Icosahedrite is a naturally occurring quasicrystal. It was first discovered in 2009 in samples of meteorites from the Khatyrka strewn field in the Koryak Mountains of eastern Russia. The mineral's chemical formula is approximately Fe72Cr24Ni30Mg1. It is characterized by its unique icosahedral symmetry, meaning it possesses five-fold rotational symmetry, which is forbidden in conventional crystalline structures. This unusual atomic arrangement gives icosahedrite its distinctive properties.

The discovery of icosahedrite was significant because it was the first naturally occurring quasicrystal found, confirming that these exotic structures could form in nature, not just in laboratory settings. Prior to this, quasicrystals were only known to be synthesized artificially. The mineral's occurrence in meteorites suggests that the conditions present during the formation of certain extraterrestrial bodies may be conducive to quasicrystal formation.

Icosahedrite is an exceptionally hard material. Its precise formation mechanism in space remains a subject of scientific investigation. Researchers continue to study icosahedrite to understand its geological origins and the implications of naturally occurring quasicrystals for materials science and planetary science.