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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.
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New NWA XXX ureilite found in 2006 was investigated by optical microscopy in reflection and in transmission. Olivines, pigeonite, metal veins and dots, and carbon phases have been revealed and their features and distribution studied. Twinning of pigeonite, reduction rims, and poikilitic inclusions of olivine in large pigeonite crystals have been identified and characterized. NWA XXX meteorite belongs to olivine-pigeonite ureilites.
EN
Average molecular weight and average atomic number of molecule of Jezersko ordinary chondrite (H4 S2(3) W2, find in 1992 in Slovenia) have been calculated using literature data on chemical composition of the meteorite (Miler et al. 2014). It was shown that Jezersko’s = 55.58, = 27.21, and ratio / = 2.043 for composition without water. Jezersko’s silicates shown the values: = 54.08, = 21.77, and / = 2.484. Volume and radius of average Jezersko molecule, and of atom have been also determined. It was calculated that the average volume of Jezersko’s molecule Vmol = 2.515·10–29 m3, and average radius of Jezersko’s molecule Rmol = 181.5 pm. Average volume of the Jezersko’s atom Vatom = 1.117·10–29 m3, and average radius of Jezersko’s atom: Ratom = 138.5 pm. Ratio of average Jezersko’s volume of molecule to atom volume: 2.25, and ratio of radius of molecule to radius of atom: 1.31. Number of atoms in Jezersko meteorite average molecule Nmol = /Amean = /Zmean = 2.25, and for Jezersko’s silicates Nsimol = 2.48.
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.
EN
Mean atomic weight Amean of Sołtmany (L6, S2, W0) ordinary chondrite, various L6 chondrites such as: Jesenice, Girgenti, Leedey, Bruderheim, Holbrook and Modoc, as well as LL, L and H chondrites has been determined using literature data on chemical composition of the meteorites. Relationship between mean atomic weight and Fe/Si atomic ratio for ordinary chondrites has been established. It was shown that Sołtmany’s Amean = 23.97 is close to mean atomic weight of L chondrites Amean = 23.70, and is close to mean atomic weight of L6 chondrites Amean = 24.06±0.16. It has been established that Sołtmany’s Fe/Si atomic ratio (Fe/Si = 0.588) is close to Fe/Si ratio for L6 chondrites (Fe/Si = 0.598). This means that Sołtmany belongs to L6 chondrites, as previously classified. Using discovered by the author (Szurgot, 2015) dependence between mean atomic weight and uncompressed density of planetary matter it was established that grain density of Sołtmany meteorite should be equal to 3.56±0.12 g/cm3, which is about 4% lower than previously estimated by porosity data. Mean atomic weight of extraterrestrial minerals present in ordinary chondrites and in Sołtmany meteorite have been also determined.
EN
New NWA XXX ureilite found in 2006 was investigated by confocal Raman microspectroscopy to determine mineral composition of the meteorite. Olivines, orthopyroxenes, orthoclase, graphite and diamond have been identified and characterized.
EN
Mean atomic weight Amean of Jezersko (H4 S2(3) W2, find in 1992 in Slovenia) ordinary chondrite has been calculated using literature data on chemical composition of the meteorite (Miler et al. 2014) and using relationship between mean atomic weight and Fe/Si atomic ratio (Szurgot 2015c, d, e). It was shown that Jezersko’s Amean = 24.68, for composition without water. This value is close to the mean atomic weight of H chondrite finds (Amean = 24.80), and is somewhat smaller than Amean values for H4 chondrite falls (Amean = 25.09), and for H chondrite falls (Amean = 25.05) (Szurgot 2015e). Jezersko’s Fe/Si atomic ratio (0.742) leads to Amean = 24.66±0.24, which is close to the value determined by bulk composition. Jezersko’s Fe/Si atomic ratio is close to the value for H’s mean Fe/Si ratio: 0.762 for finds, and 0.807 for falls (Szurgot 2016a). This confirms that Jezersko belongs to H chondrites, as previously classified (Miler et al. 2014). Mean atomic number Zmean, and Amean/Zmean ratio of the meteorite have been also calculated. Jezersko’s Zmean = 12.16, and Amean/Zmean ratio is: 2.029 for composition without water. Jezersko’s silicates shown the values: Amean = 21.77, Zmean = 10.78, Amean/Z mean = 2.019, Fe/Si = 0.272, Amean(Fe/Si) = 21.84±0.06, and Jezersko’s Fe,Ni metal values: Amean = 56.12, Zmean = 26.19, and Amean/Z mean = 2.143. Two dependences: i) grain density dgr on Amean (Szurgot 2015a), and ii) grain density dgrain on Fe/Si atomic ratio (Szurgot 2017g), were used to predict grain density of Jezersko chondrite. It was established that dgr(Amean) leads to the values: 3.65±0.07 g/cm3 for Jezersko chondrite, 3.27±0.07 g/cm3 for silicates, and 7.83±0.07 g/cm3 for Fe,Ni metal of Jezersko meteorite. Dependence dgr(Fe/Si) predicts somewhat higher value grain density for Jezersko chondrite: 3.68±0.07 g/cm3, and 3.32±0.07 g/cm3 for silicates. All the predictions lead to the mean value of grain density for its weathering W2 degree: 3.67±0.03 g/cm3 for the whole rock of meteorite, and 3.29±0.03 g/cm3 for the silicates. It was established that due to terrestrial weathering, resulting in W2 weathering stage, Amean value of Jezersko chondrite is about 0.45 lower, Fe/Si atomic ratio is about 0.075 lower, and dgrain is about 0.06 g/cm3 lower than values for unweathered (W0) meteorite. Predicted porosity for Jezersko chondrite is: 10,1±0,7% for W2, and 11,5±0,5% for W0.
EN
NWA 4967 carbonaceous chondrite thin section was investigated by optical microscopes in transmission and in reflection. Minerals of the meteorite have been identified and microstructure analyzed. Chondrules, matrix, metal phases, AOAs and CAIs are constituents of the rock, as expected. Olivine, clinopyroxene, orthopyroxene, troilite, kamacite and feldspar have been detected. Various types of chondrules including: PO, POP, PP, RP, BO, C, GOP and GO chondrules were identified. Compositional zoning of some olivines, diagnostic cracks in pyroxenes, clinopyroxene twins, and chondrule rims have been observed and analyzed. Our previous EPMA and Raman data as well as present optical data confirm that NWA 4967 belongs to CO3.2 chondrites, as previously classified.
EN
Mean atomic weight Amean of Vicência (LL3.2 S1W0, fall 2013) ordinary chondrite has been calculated using literature data (Keil et al. 2015) 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. It was shown that Vicência’s Amean = 22.91 for composition without water. This value is close to the mean atomic weight of LL chondrite falls, is close to Amean value of LL3 chondrite falls, and is close to Amean value of Semarkona LL3.0 chondrite. Vicência’s Fe/Si atomic ratio (0.492±0.050) leads to Amean = 23.06–23.26, which is close to the value determined by bulk composition. Vicência’s Fe/Si atomic ratio is close to the value for Semarkona’s (Fe/Si = 0.511), and is close to LL’s mean Fe/Si ratio (0.520). This confirms that Vicência belongs to LL chondrites, as previously classified. Using dependence between mean atomic weight and grain density leads to Amean = 21.89±0.54 (dgr = 3.28 g/cm3, Keil et al. 2015), and using dependence between Amean and magnetic susceptibility gives Amean = 23.01±0.24 (logc = 4.30, Keil et al. 2015). Arithmetic mean of Amean (dgr), Amean (logc), and Amean(Fe/Si), gives 22.72±0.73, the value close to Amean(bulk composition) determined using compositional data. Mean atomic number Zmean, and Amean/Zmean ratio of the meteorite have been also calculated. Vicência’s Zmean = 11.37, and Amean/Zmean ratio is: 2.015 for composition without water. Vicência’s silicates shown the values: Amean = 21,67, Zmean = 10.76, Amean/Z mean = 2.014, Fe/Si = 0.318, Amean(Fe/Si) = 22.07–22.18, and Fe, Ni metal values: Amean = 56.63, Zmean = 26.53, and Amean/Z mean = 2.135. Two dependences: i) grain density dgr on Amean, and ii) grain density dgr on Fe/Si atomic ratio, were used to determine/verify grain density of Vicência chondrite. It was established that dgr(Amean) leads to the values: 3,42 g/cm3 for Vicência chondrite, 3,25 g/cm3 for silicates, and 7,90 g/cm3 for Fe, Ni metal of Vicência meteorite. Dependence dgr(Fe/Si) predicts density for Vicência chondrite: 3,47–3,49 g/cm3, and for silicates: 3,32–3,35 g/cm3.
EN
New NWA XXX ureilite was investigated by analytical electron microscopy to determine elemental and mineral composition of the meteorite. The main minerals: olivines and clinopyroxenes have been identified and characterized. The texture, elemental and mineral composition of the meteorite are typical of olivine-pyroxene achondrites.
EN
Ordinary chondrite NWA 4560 was investigated by analytical electron microscopy. Elemental composition and mineral composition have been analyzed. Kamacite, troilite, olivine, orthopyroxene, clinopyroxene, and oligoclase have been identified, and mean composition of meteorite, and composition of olivine, pyroxenes and oligoclase determined. Olivine Fa30–38, orthopyroxene bronzite Fs9–32Wo2–4, clinopyroxenes (pigeonite Fs13–17Wo5–7, as well as augite Fs17Wo22), and oligoclase Ab80An20 have been found in the meteorite. Olivine and pyroxene are common. POP, PO, BO, PP, RP, C, POP, GP and GOP chondrules have been identified. Elemental and mineral composition, atomic ratios and microstructure indicate that NWA 4560 is a type 3.2 ordinary chondrite which belongs to LL group.
EN
New NWA 4039 eucrite found in 2005 in Morocco was investigated by scanning electron microscopy. Elemental composition and mineral composition have been analyzed. The composition of feldspars and plagioclases has been determined, and the presence of ilmenite, chromite, troilite and silica confirmed. It was established that the mean elemental composition of NWA 4039 and atomic and molar ratios: Fe/Mn = 31, Na/Al = 0.045, Ca/Al = 0.66 and Mg/Mg+Fe = 31 are typical of eucrites, and two main meteorite minerals have the mean composition: pyroxene En30Fs66Wo4 and plagioclase feldspar An91Ab9. Presence of clinopyroxene pigeonite En37Fs55Wo8 and plagioclase An90Ab10 and An92Ab8 has been revealed. Mean chemical composition, as well as TiO2 content (0.59 wt%) vs. FeO/MgO ratio (4.11) indicate that NWA 4039 is a non cumulate, basaltic eucrite.
EN
Carbonaceous chondrite NWA 4967 was investigated by confocal Raman micro-spectroscopy. Olivine (Fa0-68), orthopyroxene with high En95-100 and low enstatite content En25-58, clinopyroxene, plagioclase, withlockite, cristobalite, coesite, graphite and diamond have been identified and characterized. Two groups of olivines have been detected: one with high Fo content Fo80-100 and another with relatively high Fa content Fa30–68. Diamond is common and exhibits the wide range of Raman shift between 1298 and 1339 cm–1 with dominant peak at 1332 cm–1 as in the case of terrestrial diamonds. Distributions of Raman peaks for olivines and carbon phases have been analyzed.
EN
Carbonaceous chondrite NWA 1465 and eucrite NWA 4039 were investigated by confocal Raman microspectroscopy to identify the extraterrestrial minerals. Olivines, orthopyroxenes, clinopyroxenes, plagioclase, graphite, magnetite and troilite have been identified and characterized.
EN
New NWA 4967 carbonaceous chondrite found in 2007 was investigated by scanning electron microscopy. Elemental composition, mineral composition and microstructure have been analyzed. The composition and distribution of olivines have been determined, and kamacite, taenite, troilite, spinel and melilite identified.
EN
Ordinary chondrite NWA 4047 was investigated by confocal Raman microspectroscopy to identify the extraterrestrial minerals. Olivines, orthopyroxenes, clinopyroxenes, plagioclase, graphite and diamond have been identified and characterized.
EN
Ordinary chondrites DaG 610 and NWA 869, as well as graphite nodules from Canyon Diablo iron meteorites were investigated by confocal Raman microspectroscopy in order to identify extraterrestrial minerals. Olivines, orthopyroxenes (enstatite, bronzite and hyperstene), clinopyroxenes (pigeonite), plagioclase, troilite and various carbon phases, mainly graphite and diamond have been identified and characterized.
EN
Ordinary chondrite NWA 4505 was investigated by confocal Raman micro-spectroscopy. Olivine (Fa0–22), orthopyroxene (Fs6–26), anorthoclase, HT plagioclase, whitlockite, graphite and diamond have been identified. Olivine and orthopyroxene are common and exhibit wide range of Raman shift. Distributions of Raman peaks for olivines and pyroxenes have been analyzed. Narrow, well defined bands of low Ca pyroxenes and olivines indicate on the high structural order and on the high petrologic type of chondrite. The wide range of Fa content in olivine and Fs in pyroxene may indicate that NWA 4505 is an unequilibrated ordinary chondrite.
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