1Chi Ma,2,3Alan E. Rubin
American Mineralogist 107, 1030-1033 Link to Article [http://www.minsocam.org/MSA/AmMin/TOC/2022/Abstracts/AM107P1030.pdf]
1Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, U.S.A.
2Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, California 90095-1567, U.S.A.
3Maine Mineral & Gem Museum, 99 Main Street, P.O. Box 500, Bethel, Maine 04217, U.S.A.
Copyright: The Mineralogical Society of America
Zolenskyite (IMA 2020-070), FeCr2S4, 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
Fe0.99Mn0.04Ca0.01Cr1.99S3.98. The ideal formula is FeCr2S4. Electron backscatter diffraction shows that
zolenskyite has the C2/m CrNb2Se4-Cr3S4-type structure of synthetic FeCr2S4, which has a = 12.84(1) Å,
b = 3.44(1) Å, c = 5.94(1) Å, β = 117(1)°, V = 234(6) Å3, and Z = 2. The calculated density using the
measured composition is 4.09 g/cm3. 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.