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EN
This scientific paper aims to systematize knowledge about the circumstances of meteorite falls in 2018. Eight of them were officially confirmed by The Meteoritical Society: Hamburg (USA), Ablaketka (Kazakhstan), Aba Pan (Nigeria), Mangui (China), Ozerki (Russia), Renchen (Germany), Gueltat Zemmour (Morocco), Komaki (Japan). Seven more have not yet been classified: Central Kalahari (Botswana), Glendale (USA), Benenitra (Madagascar), Bhakkar (Pakistan), Ghadamis (Libya), Elkouran (Morocco) and meteorite fall from the Sahara Desert. It turns out that the most numerous group of meteorite falls in 2018 were L6 chondrites. There were no iron or stony-iron falls. The author collected information from many different sources. He analyzed entries in the MetBull catalog, publications in social media and press reports in order to compare them with official data from previous years. In this way, he tries to prove that although the circumstances of each meteorite fall are different, coherent conclusions can be drawn from them, and these can help meteorite researchers, for example, in verifying eyewitness accounts.
EN
In the highlands of the country in which the study area found was affected by soil erosion and desertification. This problem on the environment includes loss of soil fertility, reduction of the depth of water body (lakes, ponds, reservoirs etc), high water turbidity, flood hazard problems etc. This study focus on mapping of soil erosion prone areas in South Gondar zone (area: 14604 sq km), which comprises of Blue Nile river basin and Tekeze river basins. This study leads where the most effective soil conservation strategies should focus in the area. Based on GIS with the integration of the Multi Criteria Decision Analysis (MCDA), an attempt was made to combine a set of factors (Land use, Soil, Slope, Topographic Wetness Index, Stream Power Index, Elevation, and Curvature) to have a fruitful decision to fulfil to the stated objective. Raster based pairwise comparison method considering seven soil erosion motivating parameters have been done in Arc GIS environments. MCDA is used to quantify the raster based qualitative spatial erosion hotspot area which produced through pairwise comparison. Raster based spatial model tells that out of total watershed area, 39.31 sq km (0.27%), 33.40 sq km (0.23%), 2358.12 sq km (16.15%), 11027.76 sq km (75.51%) and 1145.60 sq km (7.84%) areas are very high, High, Medium, Low and Very low prone to soil erosion respectively. This study will serve as insight to Basins/watershed decision maker and planners to alleviate soil erosion problems and its related hazards.
EN
The article presents the most important facts about Polish meteoritics that took place in the 19th and 20th centuries. The text also presents issues related to the popularization of meteorites and meteoritics.
EN
Mössbauer spectra of equilibrated ordinary chondrites consist of two sextets due to magnetically ordered iron present in metallic phases and troilite and two doublets due to paramagnetic iron present in olivines and pyroxenes. The Mössbauer spectral areas of the different mineralogical phases in meteorites are proportional to the number of iron ions present in olivines, pyroxenes, metallic phase and troilite. This property of Mössbauer spectra was the basis for constructing various methods for the classification of ordinary chondrites. Review of these methods will be presented.
EN
Based on petrological, mineralogical and geochemical research authors classified new meteorite Northwest Africa 11779 as the ordinary chondrite L6, S1, W1. Chemical composition of olivine crystals (Fa 24.9 mol.%) and of pyroxene crystals (Fs 19.4 mol.%) proved that this meteorite belongs to L chondrites. However, bulk chemical composition of NWA 11779 is not typical for L chondrites. Nevertheless, all analyzed elements (except Mo, Sn and Nb) are in abundances reported for L chondrites, some of elements have concentration closed to average abundances for L chondrites. The content of chosen, characteristic lithophile, siderophile and chalkophile elements in NWA 11779 chondrite is in most cases in accord with its typical abundance in L chondrites. Presence of poorly defined chondrules, secondary feldspar crystals larger than 50 µm in size, absence of glass within chondrules, coarse recrystallized matrix (with olivine crystals of 0.5 mm in diameter and pyroxene crystals of 0.3 mm in diameter) as well as carbon content below 0.2 wt% proved that studied meteorite belongs to the petrologic type 6. The only difference from characteristic features of petrologic type 6 in case of NWA 11779 chondrite is presence of ca. 10% of monoclinic Ca-poor pyroxenes. Undulatory extinction by olivine and absence of other shock features in this chondrite allow to determine the shock level as S1. Weathering grade of NWA 11779 was identified as W1 based on weathering of only FeNi alloy grains. The outer part of metallic grains as well as contact zones of FeNi and FeS are changed due to weathering. Between 10 and 20% of FeNi alloy grains are oxidized to iron oxides and hydroxides. These secondary products of weathering replace outer zone of FeNi grains and fill the small cracks, creating a few thin veins.
EN
A tektite is a rare natural glass that forms when an extra-terrestrial body struck the Earth. Tektites can be found in at least five widely separated locations on Earth, which are called strewn fields. There are four known strewn fields: the 35.5 Ma North American strewn field (linked to the Chesapeake crater, North America), the 14.4 Ma Central European strewn field (linked to the Ries crater in Germany), the Ivory Coast strewn field of unknown age (linked to the Bosumtwi crater in Ghana, West Africa), and the 0.8 Ma Australasian strewn field (source crater still unknown, although a large crater in Western Cambodia, Lake Tonle Sap, has been proposed). The last strewn field is known for the distribution of the biggest tektite group (i.e., philippinites, billitonites, javanites, indochinites). A tektite on Havelock Island in India, has also been recently identified. This is the first tektite reported from the Andaman and Nicobar islands. This tektite is composed of indochinite, having a typical dark colour and diagnostic chemical composition. Morphologically, a lack of cracks and abraded edges, both indicate short transport and rapid shallow burial.
EN
Mössbauer 57Fe measurements of three ordinary chondrites type L were performed at room temperature. The measurements were repeated in the same experimental conditions. The experimental spectra were elaborated with „Recoil” program. The absorption areas of the same ordinary chondrite samples were very similar. The maximum variation was about 2% for doublets (paramagnetic iron) and 3% for sextet (magnetically ordered iron).
EN
Odessa iron meteorite was investigated with scanning electron microscopy (SEM), Raman spectroscopy and X-ray diffraction (XRD) techniques. The research has shown the existence of minerals such as schreibersite, troilite, taenite, kamacite, cohenite, graphite and diamond in the examined sample. Raman spectroscopy allowed to identify different allotropic forms of carbon, which is diamond and graphite with different levels of order.
EN
Weathering meteorites in different collections carried out in various ways. Its course depends mainly on the conditions which exist in a room, where meteorites are stored as well as on their construction. An important role is also the time. In Saint-Aubin iron meteorite, as a result of weathering, were formed iron hydroxides, mainly akaganeite (beta-Fe3+ (O, OH, Cl)), that occurs in the intergranular spaces and cracks. On plate surfaces of the meteorite Zegdou hydrated magnesium sulfate (most likely epsomite) (MgSO4·7(H2O)) are formed. The thin slice of the Zegdou meteorite stored in a room at constant temperature (about 20°C) and low air humidity underwent significantly, a slower degradation in relation to the tiles of the same meteorite stored in a room variable temperatures and high atmospheric humidity. The differences were observed already over several years.
PL
Wietrzenie meteorytów w zbiorach kolekcjonerskich przebiega w zróżnicowany sposób. Jego przebieg jest uzależniony głównie od warunków, jakie panują w pomieszczeniu gdzie meteoryty są przechowywane, od upływu czasu oraz od ich budowy. W meteorycie żelaznym Saint-Aubin w wyniku wietrzenia, w przestrzeniach międzyziarnowych i szczelinach, wykształcają się wodorotlenki żelaza, głównie akaganeit (beta-Fe3+ (O, OH, Cl)). Na powierzchniach płytek meteorytu Zegdou powstaje uwodniony siarczan magnezu (najprawdopodobniej epsomit) (MgSO4·7(H2O)). Płytka meteorytu Zegdou przechowywana w pomieszczeniu, w stałej temperaturze (ok. 20°C) i niskiej wilgotności powietrza, ulegała znacznie wolniejszej degradacji w stosunku do płytki tego samego meteorytu, przechowywanego w pomieszczeniu o zmiennych temperaturach i podwyższonej wilgotności. Różnice obserwowano już w przeciągu kilku lat.
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The authors drew attention to the classification in December 2022 of over one ton of lunar meteorites that fell to Earth. They have been found since the early 1960s, but their first classification, as lunar meteorites, was made only in 1982. This was possible thanks to more advanced geochemical research and the possibility of comparing their results with the results of analyzes of samples of rocks and lunar regolith brought by the Soviet missions of the Luna program, and above all by several American missions of the Apollo program. With access to over 1.4 tons of lunar rocks on Earth, we are now able to conduct multidisciplinary studies of the lunar geology. Their results are particularly important in the context of building human settlements or lunar bases for further exploration of the solar system. This applies to both the physical properties of these rocks, as well as their chemical and mineral composition in the context of the presence of deposits of various mineral resources. It should be emphasized that meteoritic material from the Moon has been increasing in terrestrial collections (especially scientific ones) very quickly since 2015. This is the result of extensive exploration work, primarily in Antarctica, Africa, the Arabian Peninsula and Australia. Among the identified rocks reaching the Earth in the form of lunar meteorites, the most numerous are feldspar breccias (impact metamorphic rocks), anorthosites (plutonic igneous rocks building highlands areas of the silver globe) and basalts (extrusive igneous rocks building areas of the lunar maria). In addition, there are other igneous mafic rocks, such as gabbro, norite, troctolite and others. The surface of the crust is covered with regolith composed of fragments of the above-mentioned igneous rocks and breccias subjected to fragmentation by successive collisions with meteorites and micrometeorites and the action of solar wind particles (space weathering). As a result of these processes, the surface of the Moon is covered with a layer of loose sedimentary rock with a thickness of a few to several meters. Locally, a regolith may be a compact clastic sedimentary rock if a significant number of rock fragments are welded together with the glaze produced during collisions with micrometeorites. The authors also briefly presented the genesis and evolution as well as the geological structure of the Moon based on the results of the latest geophysical and geochemical (including isotopic) as well as mineralogical and petrological research. They pointed out that the proposed model of the genesis of the Moon from synestia formed after the collision of the proto-Earth with another hypothetical planetary embryo called Theia, explains well the chemical and isotopic homogeneity of the Earth and the Moon. The authors also pointed out that due to the common genesis, lunar meteorites are classified and named in the same way as terrestrial rocks, which definitely distinguishes them from other meteorites. The exceptions are Martian and HED meteorites, which are classified similarly to terrestrial rocks, although their names often do not have equivalents in the classification of terrestrial rocks (e.g. SNC meteorites). Tracking data on officially classified lunar meteorites, the authors found that in December 2022, the total mass of meteoritic matter considered to coming from the Moon exceeded 1 ton. Lunar meteorites are currently the largest source of information about the geology of the Silver Globe, accounting for almost two-thirds of the mass of lunar material available for study on Earth.
PL
Autorzy zwrócili uwagę na sklasyfikowanie w grudniu 2022 roku już ponad tony meteorytów księżycowych, jakie spadły na Ziemię. Znajdowane były one od początku lat sześćdziesiątych XX wieku, jednak pierwsze ich klasyfikacje jako meteorytów księżycowych wykonane zostały dopiero w 1982 roku. Możliwe to było dzięki bardziej zaawansowanym badaniom geochemicznym i możliwości odniesienia ich wyników do wyników analiz prób skał i regolitu księżycowego przywiezionych przez misje radzieckie programu Łuna, a przede wszystkim przez kilka misji amerykańskich programu Apollo. Dzięki dostępowi na Ziemi do ponad 1,4 tony skał księżycowych możemy obecnie prowadzić multidyscyplinarne badania geologii Księżyca. Ich wyniki są szczególnie ważne w kontekście budowy osiedli ludzkich lub baz na Księżycu w celu dalszej eksploracji Układu Słonecznego. Dotyczy to zarówno właściwości fizycznych tych skał, a także ich składu chemicznego i mineralnego w kontekście występowania złóż różnorodnych surowców mineralnych. Należy podkreślić, że materiału meteorytowego z Księżyca przybywa w ziemskich kolekcjach (zwłaszcza naukowych) bardzo szybko dopiero od roku 2015. Jest to efektem szeroko zakrojonych prac poszukiwawczych przede wszystkim na obszarze Antarktydy, Afryki, Półwyspu Arabskiego i Australii. Wśród zidentyfikowanych skał docierających na Ziemię w postaci meteorytów księżycowych najliczniej reprezentowane są brekcje skaleniowe (impaktowe skały metamorficzne), anortozyty (skały magmowe głębinowe budujące wyżynne obszary Srebrnego Globu) oraz bazalty (skały magmowe wylewne budujące obszary mórz księżycowych). Poza tym spotykane są inne skały magmowe zasadowe, takie jak gabro, noryt, troktolit i inne. Powierzchnię skorupy pokrywa regolit złożony z fragmentów wymienionych skał magmowych i brekcji poddanych rozdrabnianiu kolejnymi zderzeniami z meteorytami i mikrometeorytami oraz działaniu cząstek wiatru słonecznego (wietrzenie kosmiczne). W wyniku tych procesów powierzchnia Księżyca pokryta jest warstwą luźnej skały osadowej okruchowej o miąższości od kilku do kilkunastu metrów. Lokalnie regolit może być skałą osadową okruchową zwięzłą, jeśli znaczna liczba okruchów skalnych ulegnie połączeniu (zespawaniu – ang. welding) szkliwem produkowanym w czasie zderzeń z mikrometeorytami. Autorzy przedstawili także krótko genezę i ewolucję oraz budowę geologiczną Księżyca w oparciu o wyniki najnowszych badań geofizycznych i geochemicznych (w tym izotopowych) oraz mineralogicznych i petrologicznych. Wskazali, że zaproponowany model genezy Księżyca z synestii utworzonej po zderzeniu proto-Ziemi z innym hipotetycznym embrionem planetarnym o nazwie Theia, dobrze tłumaczy jednorodność chemiczną i izotopową Ziemi i Księżyca. Autorzy zwrócili także uwagę, że dzięki wspólnej genezie meteoryty księżycowe klasyfikowane i nazywane są tak samo, jak skały ziemskie, co zdecydowanie odróżnia je od innych meteorytów. Wyjątek stanowią meteoryty marsjańskie oraz HED, które klasyfikowane są podobnie, jak skały ziemskie, aczkolwiek ich nazwy często nie mają odpowiedników w klasyfikacji skał ziemskich (np. meteoryty SNC). Śledząc dane na temat oficjalnie klasyfikowanych meteorytów księżycowych autorzy stwierdzili, że w grudniu 2022 roku łączna masa materii meteorytowej uznanej za pochodzącą z Księżyca przekroczyła 1 tonę. Meteoryty księżycowe są obecnie największym źródłem informacji o geologii Srebrnego Globu, stanowiąc niemal 2/3 masy materii księżycowej dostępnej do badań na Ziemi.
EN
One of criteria suggesting impact origin may be recognition of extraterrestrial matter inside or around suspected cavities. In case of Morasko some dating results throw doubt on link between craters and meteorites. Conclusion of some past research papers was that cavities were formed about 5 ka BP (e.g. palynological investigation, luminescence dating), while more or less facts testify fall in the Middle Ages (e.g. “young” charcoal pieces in crust of meteorites or shrapnel stuck in the roots of old tree). In this paper we perform comprehensive analysis of each result and check if there exists alternative explanation. During past palynological investigation, there were examined two craters. It was concluded that beginning of accumulation of sediments in smaller cavity started 5500–5000 BP. However, pollen spectrum for largest basin was different suggesting younger age. The problem is that according to bathymetric maps, samples could be collected from inner uplift (similar feature was observed inside Porzadzie and Jaszczulty, unconfirmed impact structures yet). If we compare profiles from craters with recent research (palynological study supported by radiocarbon dating) on sediments in Lake Strzeszynskie (6 km SW from Morasko) pollen spectrum seems to be similar more to results dated to <1000 BP. Especially percentage of non-arboreal pollen for both examined Morasko craters is much higher (5 times greater than it was for layer dated to 5 ka BP in Lake Strzeszynskie). Possibility of short disturbance (related to impact) cannot be excluded, but in such case any time of event should be taken into account. For small lakes (like those filling the craters) also local conditions could play important role. Analysis of luminescence dating may also discuss past conclusions. OSL method applied for samples taken from the thin layer of sand in the bottom of largest structure (under 3,9 m of organic sediments filling the crater) suggested age 5–10 ka BP for 24 aliquots. Same number of samples (24) revealed age 0–5 ka BP (13 samples with age <3 ka BP including several younger than 1 ka BP). Older dates can be explained by partial or even no zeroing, but last contact with light (zeroing signal) of sand grains (excavated from depth of almost 4 meters under organic matter) seems that might occur only during (or shortly after) the impact. It is difficult to find convincing arguments, which can undermine initial radiocarbon dating giving age <1 ka BP for 7 of 9 samples taken from the bottom layer of organic sediments from three Morasko craters. Same issue may exist with small charcoal pieces with age <2 ka BP (and several dated to ~700 BP) discovered deep in sinter-weathering crust of meteorites. Study of charcoal particles excluded their origin during post-sedimentary processes (like forest fire) unless meteorite fragments were laying directly on the surface for period between impact and wildfire (surviving whole time inhospitable climate conditions). There are two other possible explanations of charcoals. Either they were present at location as a result of past forest fire or they were produced during impact. However, similar small charcoal pieces were discovered around many craters (Kaali, Ilumetsa, Campo del Cielo, Whitecourt) and they were successfully used to estimate maximum age of those structures. During second stage of 14C dating the age obtained from three samples (taken few centimeters above the mineral bottom) was estimated ~5 ka BP. Looking for answer why these results are so different from previous once there may be mentioned at least two options. Lake sediments is difficult matter for radiocarbon dating and results may be hundreds or even thousands years older than real age. Second explanation may be that older matter (remnant of trees, paleosoil etc.), distributed around craters during impact, could be displaced by wind, rain, erosion and trapped in the bottom of cavities. The argument, which may be also against hypothesis of impact ~5 ka BP is meteorite shrapnel stuck in the roots of old tree. Result of expertise showed, that there exists mechanical damage in the wood and the only possible explanation is that meteorite has hit living tree. Maximum age, that this type of wood may preserve (inside building) is 1,8 ka while in natural environment not more than 500 years. Anyway some further examinations should be performed. The age obtained during AMS 14C dating of 2 samples from thin layer of paleosoil, discovered under overturned flap around largest Morasko crater, was ~5 ka BP. Observation that preserved layer of paleosoil is approximately 3 times thinner than thickness of modern soil may lead to conclusion that during impact top (younger) layer of organic sediments was removed and only older part “survived” in few locations close to the rim. The conclusion of the research was that dating provides maximum age of the impact (which does not exclude much younger impact <1 ka BP) so could be considered as right explanation of past discrepancies.
EN
Mean atomic weights Amean of Siena (LL5, fall 1794), Hautes Fagnes (LL5, S1, W1, find 1965) and NWA 7915 (LL5, S2, W3, find 2010) ordinary chondrites have been determined using literature data on chemical composition of the meteorites and using relationship between mean atomic weight and Fe/Si atomic ratio (Szurgot 2015). It was shown that NWA 7915 Amean = 22.80 is close to mean atomic weight of LL chondrites (Amean = 23.00), and is close to mean atomic weight of LL chondrite falls (Amean = 22.90, Szurgot 2015). NWA 7915’s Fe/Si atomic ratio (0.529) leads to Amean = 23.28 which is close to the value determined by bulk composition. This means that NWA 7915 belongs to LL5 chondrites, as previously classified (Brawata et al. 2014). Mean atomic weight Amean of Hautes Fagnes determined by bulk composition is between 23.11 and 23.35. Lower Amean value is close to Amean of LL chondrites, but higher value is the same as Amean of intermediate L/LL chondrites (23.34 for L/LL, Szurgot 2016). Hautes Fagnes Fe/Si atomic ratio and Amean(Fe/Si) are identical with those for NWA 7915 (Fe/Si = 0.529, Amean = 23.28). Amean data indicate that Hautes Fagnes can belong to LL5 chondrites, as previously classified (Vandeginste et al. 2012) or can be one of L/LL chondrites. Mean atomic weight of Siena meteorite is much higher than expected for LL chondrite. Siena’s bulk composition gives Amean = 24.47, and Amean(Fe/Si) dependence gives Amean = 24.45 (Fe/Si = 0.7345). Using dependence between mean atomic weight and grain density (Szurgot 2015) leads to Amean = 23.24 (dgr = 3.46 g/cm3, Macke 2010), and using dependence between Amean and magnetic susceptibility (Szurgot 2016) gives Amean = 23.53±0.13 (logc = 4.65±0.09, Macke 2010). Bulk composition and Fe/Si ratio indicate that Siena has the same Amean as intermediate H/L chondrites, for which Amean = 24.3 (Szurgot 2016). Grain density indicates rather L/LL intermediate group for Siena, and magnetic susceptibility indicates intermediate L/LL or L chondrites (23.34 for L/LL, and 23.67 for L, Szurgot 2016). Mean atomic number Zmean, and Amean/Zmean ratio of the three meteorites have been also determined. Siena’s Zmean = 12.104, Hautes Fagnes Zmean = 11.445–11.562, and NWA 7915’s Zmean = 11.293. Amean/Zmean ratios are: 2.022 for Siena, 2.019–2.020 for Hautes Fagnes, and 2.019 for NWA 7915.
EN
In this paper, a new mineralogical and chemical data on a new brecciated enstatite are presented. Fe-low enstite is the main pyroxene. Locally small grains of diopside were noted. The rest of silicates are represented by oligoclase and cristobalite. Siliceous glass was also found. The meteorite contains up to11.5 vol.% of Ni-kamacite (up to 6.8 wt.% of Ni and up to 2.9 wt.% of Si). Niningeryt and Cr-rich troilite are the main sulphides. Small amount of graphite forms a bundle-like agregates of fine plate crystals. The classification is still in progres. The new meteorite from Algeria can be an example of unbrecciated enstatite or ungrouped achondrites.
EN
On 31 January 1868, a bright fireball was observed over Poland and tens of thousands of meteorites fell northeast of the town of Pułtusk. Immediately after the fall, locals from Pułtusk went out to collect the meteorites estimated to number between 70,000 to 180,000 individual specimens. Pieces ranged from a single gram to 9 kg. The Zambrzycki family who were local land owners traded the largest mass of Pułtusk specimens to various international museums. Study shows information form institutions including Bonn, Berlin, London, Vienna, Paris, Smithsonian (Washington) and Stockholm. This paper documents the world’s biggest collections of Pułtusk specimens, and the provenance of specimens listing the original dealers, collectors and scientist who provided specimens to the various museum and institutional collections at the time.
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The Kara crater is located near the Kara Sea. Together with the Ust-Kara crater, both structures are considered a twin structure, which is rarely found on Earth. The Ust-Kara is an undersea crater, while the Kara was formed in sedimentary rocks, in wet tundra. This environment determines the distinct petrological characteristics of the Kara impactites. Large shatter cones are a characteristic feature of an impact crater. High- and low-temperature tagamites with variable amounts of melt or glass and with the fluidal texture of rocky clasts were described from the crater. The mineralization represented by pyrite and chalcopyrite occurs in the suevite breccias expressing variable amounts of glass fragments. A special feature of the Kara impactites is the presence of coal clasts and carbonate rocks as well as a secondary crystallization of calcite in the form of globules.
EN
Flooding is one of the most common natural hazards, causing disastrous impacts in Nigeria. Based on a systematic review of previous research work, this study highlights the causes of flood disaster and its effective mitigation strategies in Ilaro formation, Dahomey Basin southwestern Nigeria. The findings revealed that in most cases in Nigeria, flood disaster is caused by natural and human activities such as excessive rainfall, poor drainage facilities, poor waste disposal practices and weak policy implementation by institutions concerned with flood management. The study further revealed that increasing deforestation, and inability of land developers to adhere to physical development plans and schemes also caused flood disaster in the study area. The study concludes that flood disaster in Ilaro Formation affect physical developments such as houses, roads and other structures. In cases of serious flooding, lives can be lost in the process. This study recommends more community-based approaches to help raise environmental awareness and support the affected community residents through grants from government and donor agencies as this would enhance their coping strategies for curbing the problems and indeed remediating the flood disaster in the area. It was also suggested that land development control activities should be taken seriously to avoid the erection of developments on flood plains and flood prone areas.
EN
An anonymous person from Częstochowa in Poland found a new meteorite during the summer of 2008. The specimen was found in eolian sand, where exotic grains connected with glacial activity were not observed. The suspected meteorite was kept in the founder’s possession until the autumn of 2018. This was when the holder of the meteorite contacted the owners of the woreczko.pl webpage, which is dedicated to meteorite identification. Moreover, the webpage was developed and operated by meteorite collectors Jan Woreczko and Wadi. After meeting, Jan and Wadi bought the meteorite, which is now part of their collection. After the meeting, Jan and Wadi bought the meteorite (total meteorite mass 2143 g), which is now part of their collection. Three fragments with their total mass 20.74 g as well as two thin-sections (7.03 g) are deposited at the Earth Sciences Museum, University of Silesia in Katowice. The fusion crust is black to brownish, typical for a chondrite. Regmagliptes are visible. The meteorite is characterized by chondrules, which range in diameter from 0.015 to 1.000 mm in diameter. The most common type of chondrule is represented by olivine (Ol). The barred Ol texture, showing elongate, sub-parallel bars of olivine with clear pyroxenes (Px) and oligoclase between the bars. The second characteristic type is represented by Ol-Px porphyritic chondrules and radial Px chondrules. The matrix is not recrystallized; and the clasts are up to 0.1 to 0.2 mm in diameter. Px and Ol, plagioclase, metallic phases, troilite, and spinel (Cr-spinel) are up to 71.9 vol.%, 11.2 vol.%., 7.0 vol.%., 4.2 vol.%., and 1.1 vol.% of the meteorite, respectively. The average content of the secondary minerals is 4.4 vol.% (close to the outermost part is up to 8–10 vol.%. The meteorite is classified as a H5 ordinary chondrite, based on the Ol and Px composition (Fa/Fs), with an official name ‘Kuźnica’.
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Brothers: Jan Śniadecki (1756–1830) and Jędrzej Śniadecki (1768–1838) were prominent Polish scientists. They were Wilnius University professors. There were also meteorites in the circle of their interests.
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