Discovery of zolenskyite (FeCr₂S₄), a new sulfide mineral in the Indarch enstatite chondrite

Abstract

During a nanomineralogy investigation of the Indarch EH4 enstatite chondrite, a new sulfide mineral, monoclinic FeCr₂S₄, named “zolenskyite”, was discovered in the matrix. It has a C2/m CrNb₂Se₄-Cr₃S₄-type structure. Synthetic FeCr₂S₄ and (Fe_(0.6)Cr_(0.4))Cr₂S₄ with the monoclinic structure have been reported [1,2]. Presented here is the first natural occurrence of this phase as a new mineral in a chondritic meteorite. A field-emission analytical scanning electron microscope, electron back-scatter diffraction (EBSD) and electron probe microanalyzer (EPMA) were used to characterize its composition and structure and associated phases. The new mineral has been approved by the IMA-CNMNC (IMA 2020-070) [3]. The mineral name honors Michael E. Zolensky, an esteemed cosmochemist and mineralogist at NASA’s Johnson Space Center, for his contributions to research on extraterrestrial materials, including enstatite chondrites. A full paper on zolenskyite is under revision for American Mineralogist [4].