Leoncin – nowy polski chondryt LL4-6
Leoncin – the new LL4-6 ordinary chondrite from Poland
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In this study, the new ordinary chondrite LL4-6 from the Leoncin Community, Poland is reported. This meteorite was sold on Allegro, a Polish online e-commerce platform, to a person, who is member of the Meteoritic Society of Poland. The meteorite was sold in 2017, but originally the fall was in 2012. Finder of the meteorite from the Nowe Gniewniewice Village (Leoncin Community) claimed that the meteorite was still warm (the higher temperature was result after hit in the roof) after fall and made a whole in metal roof (which was repaired soon after the fall). For five years after fall of the meteorite, it stayed in the finder hands. The total known weight of the meteorite is 111.3 g. The main mass is in the M. Burski’s collection (~70 g). Two plates with the total mass 20 g are stored at the Earth Science Museum, Faculty of Natural Sciences, University of Silesia in Katowice, Poland. The meteorite is strongly brecciated. All clasts are rounded, reaching up to 1 cm in size. The matrix is very fine grained. The biggest as well as clasts are represented by complex olivine-feldspar chondrule. Numerous clasts do not have any chondrules or their fragments as well. The fusion crust of the Leoncin meteorite is typical, having porous and glassy (isotropic) the most external part. The glassy zone is rich in Cr-rich spinels, where relicts of unmolten olivines and pyroxenes are present. The next zone is so-called the black vein zone. The veins are represented my metallic phases or Fe sulphide. The most common mineral in the fresh meteorite is olivine, having Fo and Fa up to 69 and 31, respectively. Pyroxenes are characterised by a general chemical formulae as follow: Fs9.78–9.7 Wo44.77–44.2 En46.02–45.53. Almost all feldspars are represented by plagioclases (Ab83.5–86.76Or2.54–5.53An9.42–12.5). Metallic phases are mostly represented by kamacite, taenite and rare tetrataenite (the richest in Ni phase; 55.92–49.21 wt.%). Troilite, spinel, ilmenite, apatite and merrillite are also noted. Based on chemical composition of investigated minerals, the Leoncin meteorite can by classified as a LL ordinary chondrite. It has been confirmed by fayalite content (avg. 30.33%) as well as the forsterite content in pyroxenes (avg. 25.32%). Brecciating of the meteorite, the same mineral content of the chondrules and their matrix shows that the meteorite is an example of monomictic breccia. Metamorphic changes of the clasts, their quality, size and mineral content, together with the chemical composition of selected minerals, indicate the LL4-6 type of the meteorites. The Leoncin meteorite seems to be a regolith, that formed far from the collision place on the asteroid. This situation is confirmed by the limitation of gassy material only to the fusion crust and lack of shock changes in the minerals. The parent body might be similar to the 25143 Itokawa asteroid or has connection with the Flora family.
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