Unusual faceting on α-iron crystals found on the Moon
Channel: bhadeshia123
Date: 10/07/2023

Crystallographic analysis of scanning electron microscopy images of small μm-sized single crystals of b.c.c. iron found on the surface of the Moon shows that the deltoidal icositetrahedron faceting behaviour clearly seen is best describable as being from planes of the {229} form. While possibly unexpected given the lack of any report of such faceting in terrestrial and meteoritic b.c.c. iron single crystals, this deltoidal icositetrahedron faceting behaviour can be rationalised straightforwardly in terms of the local chemical conditions which will have been experienced by these crystals while growing from the vapour in the part of the lunar environment from which these samples were obtained.

Κ. Μ. Knowles and H. K. D. H. Bhadeshia
Journal of Crystal Growth 617 (2023) 127257
https://www.phase-trans.msm.cam.ac.uk/2023/moon.html