Hedenbergite
Iron-rich pyroxene mineral
Hedenbergite, CaFeSi2O6 (CaFe(SiO3)2), is the iron-rich end member of the pyroxene group having a monoclinic crystal system. The mineral is extremely rarely found as a pure substance, and usually has to be synthesized in a lab. It was named in 1819 after M.A. Ludwig Hedenberg, who was the first to define hedenbergite as a mineral.
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