Anorthite‐spinel‐rich inclusions in the Ningqiang carbonaceous chondrite: Genetic links with Type A and C inclusions

Abstract— Many Ca‐Al‐rich inclusions (CAIs) were molten once, and the question of what their precursors consisted of is controversial. In this paper, we report a new type of anorthite‐spinel‐rich inclusion (ASI) in the Ningqiang carbonaceous chondrite. The modal and bulk compositions of the ASIs are similar to those of Type C inclusions but with nonmolten textures. The ASIs are proposed to be the precursors of Type C inclusions. The ASIs show alteration textures, with melilite being replaced by anorthite and Ca‐pyroxene. Furthermore, compositions of the melilites and the calculated modal and bulk compositions of the possible precursors of the ASIs are close to those of the spinel‐rich Type A inclusions in the Ningqiang meteorite, which suggests that ASIs formed by alteration of the latter in the solar nebula. Petrography and mineral chemistry of one Type C inclusion in Ningqiang are also reported.