Characterization of primary silicate minerals in Earth-like bodies via Raman spectroscopy

The examination and identification of silicate minerals are critical for advancing our understanding of the evolutionary journey of Earth-like bodies. To facilitate an efficient and productive process, it is imperative that these minerals be detected swiftly and accurately. This study is designed to explore the relationship between varying concentrations of cations and their corresponding Raman shifts. The focus is on primary silicate minerals in Earth-like bodies, specifically olivine, pyroxene, and feldspar, utilizing data from the RRUFF database. Employing a fitting formula, we identify distinct Raman peak ranges associated with different silicate minerals. Our research covers a wide array of mineral types, including five varieties of olivine (forsterite [Mg₂SiO₄], fayalite [Fe²⁺₂SiO₄], tephroite [Mn²⁺₂SiO₄], monticellite [CaMgSiO₄], and kirschsteinite [CaFe²⁺SiO₄]), four types of pyroxene (ferrosilite [Fe²⁺₂Si₂O₆], enstatite [Mg₂Si₂O₆], hedenbergite [CaFe²⁺Si₂O₆], and diopside [CaMgSi₂O₆]), and three varieties of feldspar (alkali feldspar [KAlSi₃O₈], albite [NaAlSi₃O₈], and anorthite [CaAl₂Si₂O₈]). The accuracy of matching Raman characteristics is exceptionally high for all olivine and pyroxene types (100%) and an impressive 86% for feldspar. The findings from this study highlight the crucial role of Raman spectroscopy in the field of silicate mineralogy and suggest significant implications for enhancing future exploration missions to Earth-like bodies.