Abstract The Parauapebas meteorite, third official meteorite discovered in the Brazilian Amazon region, is a “hammer meteorite” which fell on December 9th, 2013, in the city of Parauapebas, Pará State, Brazil. Mineralogy is dominated by forsterite, enstatite, iron, troilite, and tetrataenite. Albite, chromite, diopside, augite, pigeonite, taenite, and merrillite are minor components. Two main clasts are separated by black shock-induced melt veins. One clast exhibits an abundance of chondrules with well-defined margins set on a recrystallized matrix composed mostly of forsterite and enstatite, consistent with petrologic type 4 chondrites. The other clast displays chondrules with outlines blurring into the groundmass as evidence of increasing recrystallization, consistent with petrologic type 5 chondrites. The clasts of petrologic type 4 have a fine-grained texture compared to those of type 5. It is a genomict breccia (indicated by shock melt veins) with the clasts and matrix of the same compositional group, but different petrologic types, H4 and H5. The melted outer crust of the Parauapebas meteorite is comprised of forsterite with interstitial dendritic iron oxide, and is rich in irregular vesicles, which are evidence of the rapid formation of the crust. The type specimen is deposited in the Museum of Geosciences of the University of São Paulo, Brazil.

ABSTRACT Serra Pelada is the newest Brazilian eucrite and the first recovered fall from Amazonia (State of Pará, Brazil, June 29th 2017). In this paper, we report on its petrography, chemistry, mineralogy and its magnetic properties. Study of four thin sections reveals that the meteorite is brecciated, containing basaltic and gabbroic clasts, as well of recrystallized impact melt, embedded into a fine-medium grained matrix. Chemical analyses suggest that Serra Pelada is a monomict basaltic eucritic breccia, and that the meteorite is a normal member of the HED suite. Our results provide additional geological and compositional information on the lithological diversity of its parent body. The mineralogy of Serra Pelada consists basically of low-Ca pyroxene and high-Ca plagioclase with accessory minerals such as quartz, sulphide (troilite), chromite - ulvöspinel and ilmenite. These data are consistent with the meteorite being an eucrite, a basaltic achondrite and a member of the howardite-eucrite-diogenite (HED) clan of meteorites which most likely are from the crust asteroid 4 Vesta.

Abstract On August 14, 1967, the reporter Saulo Gomes, working at TV Tupi, went to a small city in the State of São Paulo called Buritizal to investigate reports of a meteorite fall and write a newspaper report. He actually recovered three fragments of the meteorite at a small farm. In 2014, he donated one of the fragments to the Museu Nacional of the Universidade Federal do Rio de Janeiro (MN/UFRJ). We named this meteorite Buritizal and studied its petrology, geochemistry, magnetic properties and cathodoluminescence with the intent to determine the petrologic classification of the meteorite. In this manner, the Buritizal meteorite is classified as an ordinary chondrite LL 3.2 breccia (as indicated by lithic fragments). The meteorite consists of ~ 2% of metallic Fe,Ni and many well-defined chondrules with ~ 0.8 mm in average diameter. An ultramafic ferromagnesian mineralogy is predominant in the meteorite, represented by olivine, orthopyroxene, clinopyroxene, Fe-Ni alloy, troilite and glass. The total iron content was calculated as 20.88 wt%. Furthermore, the meteorite was classified as weathering grade W1 and shock stage S3. Buritizal is the 25th observed meteorite fall recovered in Brazil, of 70 meteorites known from Brazil. Thus, the study of the Buritizal meteorite is very important and relevant for the Brazilian scientific community.

O Brasil possui 58 meteoritos catalogados pela ciência meteorítica, número bastante inferior quando se compara tal número àqueles de países da Europa e aos de países como os Estados Unidos. As amostras estudadas pertencem à coleção de meteoritos do Museu de Mineralogia Professor Djalma Guimarães -MMPDG, constituída de 17 meteoritos, 10 brasileiros, entre eles o Bocaiúva e o João Pinheiro. O meteorito Bocaiúva, encontrado em MG, é o terceiro maior em peso do Estado (64kg), foi achado por volta de 1947, na cidade homônima, a 384km de Belo Horizonte. Além da massa principal do meteorito Bocaiúva, também há, no referido museu outro fragmento catalogado como "meteorito Bocaiúva", que, na verdade, é um fragmento pertencente a outro corpo meteorítico, o João Pinheiro, ainda não catalogado. A diferença mineralógica observada em ambos, principalmente com relação às porções silicáticas do Bocaiúva, assim como inclusões fluidas e fundidas, não deixa dúvida de se tratar de meteoritos diferentes. Minerais como kamacita, taenita, troilita, schreibersita e grafita são encontrados no meteorito João Pinheiro, enquanto que, no Bocaiúva, estão presentes a forsterita, kamacita, taenita, troilita, schreibersita, pentlandita, magnetita, cromita, pigeonita, diopsídio, enstatita, plagioclásios, apatita, calcita e goethita.

Brazil has 58 cataloged meteorites for scientific studies; a low number compared to countries in Europe and the United States. The samples studied belong to a collection of 17 meteorites from the Mineralogy Museum Professor Djalma Guimarães - MMPDG in Belo Horizonte, Minas Gerais. Ten of those meteorites were found in Brazil; among them are the Bocaiúva and João Pinheiro meteorites. The Bocaiúva meteorite, the third heaviest (64kg), was found around 1947 in the town of Bocaiúva, located 384km from Belo Horizonte, in the state of Minas Gerais. Besides the Bocaiúva meteorite, there is also, in the MMPDG, another fragment cataloged as "Bocaiúva meteorite", which is actually a fragment from a different meteoritic body, called João Pinheiro, yet to be cataloged. The mineralogical differences, especially regarding the silicate portions of the Bocaiúva, as well as fluid and melted inclusions, leave no doubt that they belong to different meteorites. Minerals such as kamacite, taenita, troilite, schreibersita and graphite are found in the João Pinheiro meteorite, while in Bocaiúva are present forsterite, kamacite, taenita, troilite, schreibersite, pentlandita, magnetite, chromite, pigeonite, diopside, enstatite, plagioclase, apatite, calcite and goethite.

Resumo: O meteorito Bendegó, uma massa de ferro e níquel com 5.360 kg, é o maior exemplar da coleção brasileira e detentor de uma rica história de contribuições à ciência meteorítica. Sua descoberta em 1784 no sertão da Bahia, sua épica remoção para o Museu Nacional (Rio de Janeiro) no fnal do século XIX e sua participação em estudos que estabeleceram a classifcação química dos meteoritos metálicos na década de 1970 credenciam esse visitante espacial a reafrmar junto à comunidade geológica brasileira a importância dessas amostras extraterrestres que são autênticos arquivos repletos de informações sobre o que ocorreu nos primórdios do sistema solar e nos processos de diferenciação química dos planetas e asteróides. Este artigo estuda esse meteorito em seus contextos histórico, cósmico, geológico, petrológico e geoquímico lançando mão de técnicas analíticas avançadas a exemplo da análise por ativação de nêutrons, a espectroscopia de massa indutivamente acoplada a plasma e a microscopia eletrônica de varredura para melhor caracterizar as propriedades dessa massa de Fe-Ni que algum dia era parte integrante do núcleo de um objeto espacial sufcientemente grande para experimentar um processo de diferenciação química.

Abstract: The Bendegó meteorite, an iron and nickel mass weighting 5,360 kg, is the largest specimen in the Brazilian collection and holds a rich record of contributions to the meteoritic science. Its fnding in 1784 in the hinterland of Bahia State, its epic transportation to the National Museum (Museu Nacional, Rio de Janeiro) in the end of the XIX century, and its participation in the studies which lead to the chemical classifcation of the metallic meteorites in the 70´s, grant to this space visitor enough credibility to reinforce to the Brazilian geologic community the importance of those extraterrestrial samples, which are authentic records of the beginning of the solar system and early chemical differentiation processes of planets and asteroids. This paper presents new insights regarding the Bendegó historic, cosmic, geologic, petrologic and geochemical context and takes advantage from modern analytical methods, such as the instrumental neutron activation analysis, mass inductively coupled plasma spectroscopy, and scanning electronic microscopy, to better characterize the properties of such a Fe-Ni mass which, someday, would be the core of a space object, big enough to experiment a chemical differentiation process.