Optical Spectra of Siderite, FeCO₃ 

• Lobanov SS, Goncharov AF, Litasov KD (2015) Optical properties of siderite (FeCO₃) across the spin transition: crossover to iron-rich carbonates in the lower mantle. American Mineralogist 100, 1059–1064. 
• Taran MN, Müller J, Friedrich A, Koch-Müller M (2017) High-pressure optical spectroscopy study of natural siderite. Physics and Chemistry Minerals 44, 537–546.