THE OCCURRENCE OF GROSSITE (CAAL4O7) IN CHONDRITES

Abstract

The mineral grossite (CaAl4O7; Ca-dialuminate, also termed CA2) is a rare phase in terrestrial and extraterrestrial rocks. In meteorites, grossite was found in Ca,Al-rich inclusions (CAIs) from Allende (CV3), Vigarano (CV3), Leoville (CV3), Efremovka (CV3), Colony (CO3), Murchison (CM2), ALH 85085 (CH), Acfer 182 (CH), Acfer 059-E1 Djouf 001 (CR2), and the anomalous C-chondrite Adelaide. In Ca,Al-rich inclusions from most of these meteorites, grossite is an accessory phase; however, in many CAIs from ALH 85085, Acfer 182, and Acfer 059-E1 Djouf 001 it is a major phase.