Serra Pelada is the newest Brazilian eucrite and the first recovered fall from Amazonia (State of Pará, Brazil, June 29 th 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.Key words: Serra Pelada, meteorite, eucrite, Vesta, Brazilian Meteorite.

The Parauapebas meteorite, third official meteorite discovered in the Brazilian Amazon region, is a "hammer meteorite" which fell on December 9 th , 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.

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Cathodoluminescence (CL) imaging is an outstanding method for sub classification of Unequilibrated Ordinary Chondrites (UOC) -petrological type 3. CL can be obtained by several electron beam apparatuses. The traditional method uses an electron gun coupled to an optical microscope (OM). Although many scanning electron microscopes (SEM) and electron microprobes (EPMA) have been equipped with a cathodoluminescence, this technique was not fully explored. Images obtained by the two methods differ due to a different kind of signal acquisition. While in the CL-OM optical photography true colors are obtained, in the CL-EPMA the results are grayscale monochromatic electronic signals. L-RGB filters were used in the CL-EPMA analysis in order to obtain color data. The aim of this work is to compare cathodoluminescence data obtained from both techniques, optical microscope and electron microprobe, on the Bishunpur meteorite classified as LL 3.1 chondrite. The present study allows concluding that 20 KeV and 7 nA is the best analytical condition at EPMA in order to test the equivalence between CL-EPMA and CL-OM colour results. Moreover, the color index revealed to be a method for aiding the study of the thermal metamorphism, but it is not definitive for the meteorite classification.

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