53-2 Occurrence and Characterization of Rare PGE and As-Bearing Phases in Chondrites

Abstract:

Chondrites preserve records of the processes of the early Solar System that are typically obscured and overprinted in other Solar System bodies. Although chondrites have been studied extensively, several aspects of their formation and evolution remain poorly understood. Due to their uniqueness, rare phases enriched in PGEs such as sulfides, tellurides, and arsenides as well as other arsenides and sulfarsenides have the potential to provide new insight into the formation conditions and/or modification processes of these meteorites. However, these phases have been generally overlooked due to their small size and rarity, resulting in mostly vague descriptions of their presence in the limited literature that acknowledges them.

Sampling CK, CV, and R chondrites, where the occurrence of these phases has been described throughout a range of thermal metamorphism, allows for investigating a range of solar nebula aspects and allows the separation of systematics in the primary condensation of these elements and secondary redistribution effects that result in the present day systematics in petrology and chemistry of these phases. The mineral compositions and textural relationships of these phases in the chondrites is constrained by optical microscopy, SEM, and compositional analysis and the systematics between the chondrites in the abovementioned chondrites is presented. The occurrences, composition, and textural relationships are used to draw conclusions and allows for a better overall understanding of the PGE, As, and Te elements in the early solar system and subsequent overprinting due to nebula and parent body processes.

© Copyright 2026 The Geological Society of America (GSA), all rights reserved.