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1
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Nowe polskie znalezisko, Częstochowa

100%
Woźniak B., Woźniak M.
Acta Societatis Metheoriticae Polonorum
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2019
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vol. 10
193-198
EN
The history of finding another Polish meteorite. The process of meteorite preparation for research and classification. Making 3D copies of the specimen and cutting it.
2
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Nowy chondryt z Libii

80%
Abu Anbar M., Kryza R., Przylibski T. A., El Bahariya G.
Acta Societatis Metheoriticae Polonorum
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2009
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vol. 1
9-12
EN
On Saturday, 21 of May, 2006, a fall was observed and the stony meteorite was found in a small crater on an apple farm at Werdama village, near Al Beda town in Libya. Based on preliminary examinations, the authors described the meteorite as an ordinary chondrite. Further research aiming at full characteristics, classification and registration of the meteorite is in progress.
3
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Klasyfikowanie chondrytów zwyczajnych – kolejność prac, metody badań, sprawy formalne i inne problemy

80%
Przylibski T. A., Kryza R., Pilski A. S.
Acta Societatis Metheoriticae Polonorum
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2011
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vol. 2
195-196
4
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Reklasyfikacja meteorytu Pułtusk

80%
Pilski A. S., Karwowski Ł., Siemiątkowski J.
Acta Societatis Metheoriticae Polonorum
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2011
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vol. 2
194
5
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Reklasyfikacja chondrytu zwyczajnego Sahara 02500

80%
Owocki K.
Acta Societatis Metheoriticae Polonorum
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2011
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vol. 2
192
6
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Nowy chondryt zwyczajny L6, S1, W1: Northwest Africa 11779

61%
Przylibski T. A., Łuszczek K., Kryza R.
Acta Societatis Metheoriticae Polonorum
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2019
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vol. 10
121-139
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.
7
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Planimetrowanie ziaren FeNi jako metoda ustalenia stopnia wietrzenia W0–W4 chondrytów zwyczajnych

61%
Przylibski T. A., Łuszczek K., Blutstein K.
Acta Societatis Metheoriticae Polonorum
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2019
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vol. 10
111-120
EN
Wlotzka scale (Wlotzka 1993) is commonly used to determine the weathering grade of ordinary chondrites. The scale is descriptive and based mostly on a subjective assessment of researcher. In this paper authors define a new, quantitative method to establish the W0–W4 weathering grade, which is based on planimetry of FeNi grains. Results of planimetry are compared with average content of FeNi metal in unweathered chondrites from the same group. Weathering grade estimated by this method are consistent with, or slightly different from the official one determined in classification, what proves the efficacy of the proposed method. Moreover, the method was applied to define weathering grade of meteoritic samples not classified so far: Pułtusk (W2), Thuathe (W2), Gao-Guenie (W2/W3), NWA 5205 (W3), NWA 4505 (W3), NWA 5296 (W2).
8
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Średni ciężar atomowy chondrytu Ensisheim (LL6)

61%
Szurgot M.
Acta Societatis Metheoriticae Polonorum
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2017
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vol. 8
110-122
EN
Mean atomic weight Amean of Ensisheim (LL6, fall 1492) ordinary chondrite has been determined using literature data on chemical composition of the meteorite and using relationships: between mean atomic weight and Fe/Si atomic ratio, between Amean and grain density, and between Amean and magnetic susceptibility (Szurgot 2015a–f, 2016a, b, d, e). It was shown that Ensisheim’s Amean = 23.32, and 23.06 for composition without water, and with H2O, respectively. These values are close to the mean atomic weight of LL chondrite falls (Amean = 23.36, and 23.03), and are close to Amean values of LL6 chondrite falls (Amean = 23.30, and 23.06, Szurgot 2016b). Ensisheim’s Fe/Si atomic ratio (0.509) leads to Amean = 23.16±0.12 which is close to the values determined by bulk composition. This means that Ensisheim belongs to LL6 chondrites, as previously classified (Jarosewich i Dodd 1985). Using dependence between mean atomic weight and grain density (Szurgot 2015a–c, 2016d) leads to Amean = 23.70±0.54 (dgr = 3.52±0.04 g/cm3, Macke 2010), and using dependence between Amean and magnetic susceptibility (Szurgot 2016a, d) gives Ameanc = 22.78±0.24 (logc = 4.15±0.09, Macke 2010). Arithmetic mean Amean (dgr) and Amean (logc) gives 23.24±0.65, and arithmetic mean of Amean (dgr), Amean (logc), and Amean(Fe/Si), gives 23.21±0.46 values close each other, and close to Amean(bulk composition) determined using compositional data. Mean atomic number Zmean, and Amean/Zmean ratio of the meteorite have been also determined. Ensisheim’s Zmean = 11.51 for composition without H2O, and 11.40 for composition with H2O. Amean/Zmean ratios are: 2.026 and 2.023, for composition without water, and with H2O, respectively. Ensisheim’s silicates shown values: Amean = 22.19, Zmean = 10.97, Amean/Z mean = 2.022, Fe/Si = 0.355, Amean(Fe/Si) = 22.28, and Fe, Ni metal values: Amean = 57.26, Zmean = 26.96, and Amean/Z mean = 2.124.
9
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Nowy chondryt zwyczajny H5, S2, W1: Northwest Africa 11778

61%
Przylibski T., Łuszczek K., Kryza R., Blutstein K.
Acta Societatis Metheoriticae Polonorum
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2020
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vol. 11
77-97
EN
Based on petrological, mineralogical and geochemical analyses, the authors classified the new meteorite Northwest Africa 11778 as an ordinary chondrite H5, S2, W1. It is a single stone with mass 767.5 g and with well-preserved black fusion crust with brown shade (Fig. 1). This meteorite was found in Sahara Desert and it was purchased by Wroclaw University of Science and Technology, Faculty of Geoengineering, Mining and Geology from Moroccan dealer in Zagora in June 2013. The most characteristic component of analyzed chondrite are different types of chondrules (barred olivine – BO, porphyritic olivine – PO, granular olivine – GO, radial pyroxene – RP, porphyritic olivine-pyroxene – POP, cryptocrystalline – C) (Fig. 2), which constitute 75% of meteorite. Their size is in range 0.2–1.2 mm, with average chondrule size ca. 0.6 mm. Bigger porphyritic olivine chondrules with diameter up to 1.5 mm rarely occur. The chemical composition of olivine crystals (Fa 18 mol%) and pyroxene crystals (Fs 16.2 mol%) proves this meteorite to be an H chondrite (Tab. 1, Fig. 4–5, App. 1–2). The averaged concentration of major elements in the classified meteorite is comparable to their mean content in H chondrites (Fig. 8). The meteorite NWA 11778 contains only slightly less Mg and Al than average H chondrites (Tab. 2). Among the other analysed elements, values distinctly out of the range of typical concentrations for H chondrites are characteristic of Hg and Eu (lower concentration in the NWA 11778 meteorite) (Tab. 3, Fig. 8–9). The presence of chondrules with predominantly sharp boundaries (Fig. 2), secondary feldspar crystals with sizes of up to 50 mm, chiefly crystalline mesostasis and only secondarily – devitrified glass in chondrules, and transparent crystalline matrix (with olivine crystals up to 0.26 mm and pyroxenes up to 0.30 mm in size), as well as common occurrence of untwinned rhombic pyroxenes prove the classified meteorite to belong to petrological type 5. It is additionally confirmed by mean Ni content in troilite below 0.5 wt% (0.04 wt%) (Tab. 1, App. 4) and carbon content below 0.2 wt% (0.07 wt%) (Tab. 2). Undulatory extinction in some olivine and pyroxene crystals and the presence of irregular fractures in the NWA 11778 chondrite enables specifying its shock level as S2. The weathering grade adopted for the NWA 11778 chondrite was W1, as visible weathering changes cover only the marginal parts of FeNi alloy grains. As a result of the weathering of 10–20% of FeNi grains, iron oxides and hydroxides are formed. These secondary weathering Fe3+ compounds also fill cracks, forming veins running between chondrules within matrix (Fig. 3).
10
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Opis okoliczności i miejsca spadku meteorytu we wsi Sołtmany pod Giżyckiem oraz wstępne wyniki badań

51%
Woźniak B., Woźniak M.
Acta Societatis Metheoriticae Polonorum
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2012
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vol. 3
140-152
EN
A description of an ordinary chondrite L6 type fall in Soltmany Village. A report from a fall spot and initial results of examination carried by polish scientists team. An examination of elementary and mineral abundance and magnetic features. History of meteorite fragments.
11
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Skład chondrytów zwyczajnych a potencjalne surowce pasa planetoid

51%
Łuszczek K., Przylibski T. A.
Acta Societatis Metheoriticae Polonorum
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2011
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vol. 2
92-111
EN
In this article the authors present a simple method of determining the content of selected metal raw materials (Fe, Ni, Co) on the parent bodies of ordinary chondrites. Thanks to the use of planimeter for measuring, under microscope, polished slices of meteorites, it is possible to estimate quite accurately the proportion of these metals in the parent bodies of meteorites, i.e. on asteroids. When it comes to analysing a large number of polished slices, these results will be most likely comparable to much more expensive results of chemical tests conducted on meteorites. Based on the analysis of 16 thin polished sections and polished slices of 11 ordinary chondrites, the authors found out that the highest content of Fe, Ni and Co ore minerals, reaching 10,06% of the total volume, can be found in ordinary chondrites from group H. For ordinary chondrites from groups L and LL, it makes 3,86% and 3,93% of the volume respectively. Employing the results of chemical analyses available in literature sources, the authors also estimated the size of Fe, Ni and Co resources for several selected asteroids. These bodies contain higher concentrations of iron, nickel and cobalt than terrestrial deposits (those found in the earth’s crust). The total content of Fe on parent bodies of even the most deficient in metals group LL of ordinary chondrites is about twice as high as that in the earth’s crust. Cobalt occurs on parent asteroids of ordinary chondrites in concentrations 15–24 times as high as those in the earth’s crust, and the concentrations of Ni are 100–180 times as high as those in the earth’s crust. The contents of these metals on parent asteroids of ordinary chondrites are also several times as high as those in currently extracted deposits in the earth’s crust. Taking into account the mean annual terrestrial production of these metals, the authors have estimated that a parent asteroid of ordinary chondrites with the size between 433 Eros and 6 Hebe could satisfy our need for Fe, Ni and Co for the nearest several million to dozens of billion years. Considering the fact that asteroid belt contains plenty of such objects, and as many asteroids built chiefly of Fe-Ni alloy, one should regard this section of the Solar System as a practically inexhaustible source of metal raw materials. The prospect of their exploitation is probably much nearer than we can currently imagine.
12
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Chondryt Sołtmany

31%
Przylibski T. A.
Acta Societatis Metheoriticae Polonorum
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2016
|
vol. 7
93-122
EN
The Sołtmany hammer meteorite is classified as an ordinary chondrite type L6, W0, S2. At present it is the most thoroughly and comprehensively examined Polish meteorite. A comprehensive petrological, mineralogical and geochemical analysis alongside the investigation of its physical and particularly thermophysical properties, and, most of all, analyses of cosmogenic radionuclides and noble gases isotopes content, as well as the use of a troilite thermometer has made it possible to draw interesting conclusions concerning the genesis and evolution of the parent body and the history of the parent meteoroid and, finally, the Sołtmany meteorite. The present report attempts at summing up the results of studies conducted at several European research centres in the last four years. The age of the the Sołtmany chondrite parent rock has been defined at 4.137 billion years. It was formed at a temperature of up to 440–450 K (about 170°C), probably at a depth of up to 3 to 7 km under the surface of the parent body, i.e. at a pressure of the order of 1–2.4 kbar. Such a low temperature during the accretion, diagenesis and metamorphism of the parent body may point to its complicated development, which may be in part due to collisions of partially melted planetesimals. Like with other type L ordinary chondrites, one can infer that the parent body could have been destroyed about 467 million years ago, at the time of a catastrophic collision which led to the formation of Gefion family of planetoids. Perhaps one of the bodies in this family was involved in another collision about 29.2 million years ago, which resulted in ejecting the parent meteoroid of the Sołtmany chondrite onto the Earth collision trajectory. Before entering the Earth’s atmosphere, this meteoroid had the mass of about 36 kg and the diameter of ca 13.5 cm. During its flight through the atmosphere, it rotated and somersaulted, which resulted in the formation of an uniform thin (0.5–0.7 mm) fusion crust, whose temperature reached 1000°C. In the last phase, the Sołtmany meteorite fell almost vertically and its mass was a mere 3% of the mass of the parent meteoroid – 1.066 kg. It hit the roof and then the concrete stairs of a farm building, which caused it to break into two bigger and many small pieces. It was found a few minutes after the fall, which occurred at 6:03 a.m. (CEST, UTC+2:00) on 30 April 2011, by Wydmińskie Lake in northern Poland (54°00,53’N, 22°00,30’E). The Sołtmany chondrite is one of just 14 meteorites in which the activity concentration of the cosmogenic 52Mn has been determined, and one of the few ordinary chondrites where the concentration of organic matter has been defined. As a result, it was found out that unlike in carbonaceous CI chondrites, the composition of organic particles is dominated by less complex compounds (CHO and CHOS) than CHNO and CHNOS compounds. This may indicate the decomposition of more complex organic compounds into particles with simple structures during magmatic and metamorphic processes related to formation of type L ordinary chondrites.
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