Zolenskyite, FeCr2S4, a new sulfide mineral from the Indarch meteorite

• Published in: The American mineralogist Vol. 107; no. 6; pp. 1030 - 1033
• Main Authors: Ma, Chi, Rubin, Alan E.
• Format: Journal Article
• Language: English
• Published: Washington Mineralogical Society of America 01.06.2022; Walter de Gruyter GmbH
• Subjects: Chemical composition; Chondrites; Electron backscatter diffraction; Electron probe; Electron probe microanalysis; Enstatite; enstatite chondrite; Extraterrestrial materials; Extraterrestrial matter; FeCr; High pressure; Indarch meteorite; Manganese; Meteorites; Meteors & meteorites; new mineral; sulfide; Sulfides; Sulphides; Survival; Tridymite; Troilite; Zolenskyite
• ISSN: 0003-004X; 1945-3027
• DOI: 10.2138/am-2022-8094

Zolenskyite (IMA 2020-070), FeCr , is a new sulfide mineral that occurs within troilite, with clinoenstatite and tridymite, in the matrix of the Indarch meteorite, an EH4 enstatite chondrite. The mean chemical composition of zolenskyite determined by electron probe microanalysis, is (wt%) S 43.85, Cr 35.53, Fe 18.94, Mn 0.68, Ca 0.13, total 99.13, yielding an empirical formula of Fe Mn Ca Cr . The ideal formula is FeCr . Electron backscatter diffraction shows that zolenskyite has the 2/ CrNb Se -Cr -type structure of synthetic FeCr , which has = 12.84(1) Å, = 3.44(1) Å, = 5.94(1) Å, β = 117(1)°, = 234(6) Å , and Z = 2. The calculated density using the measured composition is 4.09 g/cm . Zolenskyite is a monoclinic polymorph of daubréelite. It may be a high-pressure phase, formed from daubréelite at high pressures (several gigapascals) and moderate temperatures in highly shocked regions of the EH parent asteroid before becoming incorporated into Indarch via impact mixing. Zolenskyite survived moderate annealing of the Indarch whole-rock. The new mineral is named in honor of 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.