Clays are messy--also on Mars.

The Curiosity rover on Mars, landed in 2012, is capable of mineralogical investigation using X-ray diffraction, complementing the abundant infrared remote sensing data already available on clay minerals. We can, however, expect that the in situ X-ray diffraction information will convey a more complex picture than that inferred from infrared spectroscopy alone. CheMin has landed. [ABSTRACT FROM AUTHOR]