Trace Element Abundances in an Unusual Hibonite-perovskite Refractory Inclusion from Allende

Presolar isotopic and chemical signatures in hibonite-bearing refractory inclusions from the Murchison carbonaceous chondrite

Magnesium-, calcium-, and titanium-isotopic compositions, as well as trace-element abundances, have been determined by ion microprobe mass spectrometry for 37 hibonite-bearing inclusions from the Murchison carbonaceous chondrite. These and previously analyzed hibonite-bearing inclusions can be divided into three main groups based on morphological and mineralogical criteria. PLAty Crystal fragme...

Hibonite-(Fe), (Fe,Mg)Al12O19, a new alteration mineral from the Allende meteorite

Hibonite-(Fe), (Fe,Mg)Al12O19, is the Fe2+-dominant analog of hibonite CaAl12O19, discovered in a highly altered Ca-,Al-rich refractory inclusion from the Allende meteorite. It occurs as scattered micrometer-sized single crystals within an aggregate of hercynite (Fe,Mg)Al2O4, adjacent to nepheline, ilmenite, ferroan spinel, perovskite, and hibonite. The mean chemical composition determined by e...

Trace Element Abundances of Ninety Refractory Inclusions in the Allende Meteorite

Rare Earth Element Abundances in Refractory Inclusions from Y-81020 (co3.0) Chondrite: Evidence of Ree Fractionation under Variable Conditions

Introduction: In the course of the systematic study on refractory inclusions in the Ningqiang meteorite [1], ion microprobe analyses of rare earth elements (REEs) have been performed and correlated positive anomalies in Ce (+Eu) +Yb have been found in some inclusions [2, 3]. Two different patterns are recognized: one is HREE-depleted patterns with positive anomalies in Ce +Eu +Yb (named as modi...

Calcium Tschermak’s pyroxene, CaAlAlSiO6, from the Allende and Murray meteorites: EBSD and micro-Raman characterizations

Calcium Tschermak’s pyroxene (CaTs), CaAlAlSiO6, is well known as an important component in pyroxene. It is a member of the Ca clinopyroxene group in which Al dominates in the M1 site. Pyroxenes with more than 80 mol% CaTs were observed previously in Ca-,Al-rich refractory inclusions (CAI) from five carbonaceous chondrites. This study re-investigated the near end-member CaTs in the Allende and ...