Vibrational spectroscopic, crystallographic, and microscopic investigation on the Aioun El Atrouss diogenite

Diogenites are thought to have originated from asteroid 4 Vesta asteroid, and it has been previously shown that they mostly consist of orthopyroxene, chromite, and olivine minerals. In this study, the Aioun El Atrouss (AAT-1) diogenite was analyzed by vibrational spectroscopic (FT-IR and micro-Raman), EDXRF, and XRD techniques. AAT-001 is mainly composed of pyroxene and with lesser olivine. XRD investigation confirmed magnetite, kamacite, ilmenite, and albite. A troilite-orthopyroxene intergrowth was revealed by XRF. The olivine composition was estimated to be approximately Fo(66) by Raman olivine characteristic doublets. Pyroxenes in AAT-01 were found to be En(80)Fs(20). Finally, approximate peak shock pressure of more than 86 GPa for AAT-1 was suggested based on previous hypervelocity impact experiments on olivine.