Northwest Africa 15523 (NWA 15523) Purchased: 2022 May Classification: Carbonaceous chondrite (CM2) History: Reportedly found in early 2022 in Hassi Khebi, Algeria. Petrography: (K. Metzler, IfP) Chondrules, chondrule fragments, CAIs, and PCP(TCI) particles are embedded in a fine-grained black matrix (about 50 vol% matrix). The vast majority of chondrules belong to the chemical type I. Chondrule sizes are mostly between 50 and 300 µm; a few chondrules with sizes up to 1.5 mm are present. Many chondrules are mantled by fine-grained dust. Accessories are troilite, pentlandite, and calcite. Geochemistry: Mineral compositions and geochemistry: Mean olivine composition: Fa7.2±12.1 (Fa0.3-40.7); n=13. Mean composition of low-Ca pyroxene: Fs1.4±0.7 Wo2.4±1.8 (Fs0.7-2.7 Wo0.9-5.7; n=10) Classification: CM2 chondrite based on the occurrence of CAIs and PCP (TCI) particles, small chondrule size, chondrule-matrix ratio, and mineral chemistry. Shock stage: C-S2 Weathering grade: Moderate Classifier: K. Metzler, IfP. This lot has no reserve price and comes with its certificate of authenticity. Thanks for your interest.