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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.
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Nowy chondryt z Libii

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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.
EN
Morasko meteorite (IAB octahedrite) contains numerous graphite-troilite inclusions. Within these inclusions, many mineral phases have been found, including native elements, sulphides, tellurides, oxides, phosphates and silicates. Apart from dominant graphite and troilite, the following minerals occur: copper, sphalerite, daubreelite, chromite, cosmochlor, enstatite, albite and orthoclase; phosphates (buchwaldite and brianite) are found occasionally, whereas djerfischerite, altaite, olivine and silica are rare. The mineral composition of the nodules suggests a more complex origin of the Morasko-type meteorites than currently assumed.
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).
EN
Sixteen specimens of the Morasko, one specimen of Seeläsgen and one specimen of Jankowo Dolne irons were analyzed with INAA to determine contents of 14 siderophile elements. The samples selected for analyses have their structures described and the presence or absence of cohenite checked. For preliminary interpretation, we have chosen elements determined with highest accuracy: Co, Ni, Ga, As, Ir and Au. The results are shown in tables and diagrams. It has been found that there are no significant differences in composition between fragments with and without cohenite. The observed low contents if iridium are not accompanied by lower contents of elements showing similar behavior during crystallization: platinum and tungsten, which suggests that fractional crystallization was not the reason of lower iridium content. Similar concentrations of elements have been found in all the Morasko specimens, and in the Seeläsgen and Jankowo Dolne irons, which suggests that all these meteorites come from one iron shower.
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