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We analysed the recent (2019 - 2021) brecciated carbonaceous chondrite falls Flensburg (C1), Tarda (C2,) Kolang (CM1/2), Aguas Zarcas (CM2), and Winchcombe (CM2) together with Murchison and Paris for their chemical composition using ICP-MS and for Hg abundances using a direct mercury analyser. Chemical variations were evaluated considering new and published petrological and mineralogical data. Aguas Zarcas #1 is enriched in Hg relative to a CI reference value of 258 ng/g, while Flensburg, Kolang, Winchcombe and the fusion crust-rich samples Aguas Zarcas #3a and 3b are depleted. The Hg contents in Aguas Zarcas #2 and 4 and both Tarda specimens are roughly similar to those extrapolated from plateau volatile element abundances, with a best fit if a CI Hg content of about 210 ng/g is assumed. For Flensburg, Kolang, Aguas Zarcas #1 and 2, Murchison and Paris, elements analysed by ICP-MS display a typical CM composition, but Tarda shows less depletion of moderately volatile elements. Deviations for Ca, Sr, Ba, Na, Rb, and Cs in the pre-rain samples Aguas Zarcas #3a and 3b suggest that these elements were mobile within the parent body. The metal-rich lithology of Aguas Zarcas #4 displays no systematic enrichment in siderophile elements, but peculiar enrichments of refractory elements, most significantly for Zr, Hf, W, Ir, and some heavy REE. The enrichment of Ca, Sr, Mn, and Mg esp. in Tarda #1 reflects the high abundance of carbonates. Unlike for Tarda and some Aguas Zarcas samples, the Flensburg CM-related composition was not affected by intense aqueous alteration.

On April 23, 2019, a meteorite fall occurred in Aguas Zarcas, Costa Rica. According to the Meteoritical Bulletin, Aguas Zarcas is a brecciated CM2 chondrite dominated by two lithologies. Our X‐ray computed tomography (XCT) results show many different lithologies. In this paper, we describe the petrographic and mineralogical investigation of five different lithologies of the Aguas Zarcas meteorite. The bulk oxygen isotope compositions of some lithologies were also measured. The Aguas Zarcas meteorite is a breccia at all scales. From two small fragments, we have noted five main lithologies, including (1) Met‐1: a metal‐rich lithology; (2) Met‐2: a second metal‐rich lithology which is distinct from Met‐1; (3) a brecciated CM lithology with clasts of different petrologic subtypes; (4) a C1/2 lithology; and (5) a C1 lithology. The Met‐1 lithology is a new and unique carbonaceous chondrite which bears similarities to CR and CM chondrite groups, but is distinct from both based on oxygen isotope data. Met‐2 also represents a new type of carbonaceous chondrite, but it is more similar to the CM chondrite group, albeit with a very high abundance of metal. We have noted some similarities between the Met‐1 and Met‐2 lithologies and will explore possible genetic relationships. We have also identified a brecciated CM lithology with two primary components: a chondrule‐poor lithology and a chondrule‐rich lithology showing different petrologic subtypes. The other two lithologies, C1 and C1/2, are very altered and possibly related to the CM chondrite group. In this article, we describe all the lithologies in detail and attempt a classification of each in order to understand the origin and the history of formation of the Aguas Zarcas parent body., ProjektDEAL, Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659, Japan Society for the Promotion of Science http://dx.doi.org/10.13039/501100001691

On September 12, 2019 at 12:49:48 (UT) a bolide was observed by hundreds of eye-witnesses from the Netherlands, Germany, Belgium, Denmark and the UK. One day later a small meteorite stone was found by accident in Flensburg. The presence of short-lived cosmogenic radionuclides with half-lives as short as 16 days proves the recent exposure of the found object to cosmic rays in space linking it clearly to the bolide event. An exceptionally short exposure time of ∼5000 years was determined. The 24.5 g stone has a fresh black fusion crust, a low density of, Geochimica et Cosmochimica Acta, 293, ISSN:0016-7037, ISSN:1872-9533