Chlorite, this very common weird looking green mineral, is found almost everywhere. It is associated with magmatic, metamorphic, and diagenetic reactions that occur over a wide temperature range. Due to its specific chemistry, knowing the composition of this mineral allows geoscientists to estimate the temperature of its formation, making chlorite a perfect geothermometer. In addition, this mineral provides indirect evidence for the presence of water in the environment in which it forms. Well, guess what. Chlorite has been detected on Mars! So, knowing its composition can help us to understand geological processes that have occured on the red planet. The Rover Perseverance, which landed on Mars on February 2021, carries a Raman spectrometric system that allows analysis of the composition of rocks and minerals. However, interpretation of the generated dataset requires that specific mineral calibrations exist for comparison. Dr. Lacroix has been working on chlorite for more than a decade and owns a collection of chlorite samples from around the world that encompass a large range of compositions. His graduate student, Sarah Lamm, analyzed representative samples from this chlorite ‘library’, using the Geology Department’s Raman spectrometer and produced the very first Raman chlorite calibration. The results which have been recently published in Journal of Raman Spectrometry, will be very useful for planetary scientists working on Mars and other planets. Sarah is now Ph.D student at the University of Kansas and continues her path to Planetary Science.
