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from
The Meteoritical Bulletin, no. 103
Abar al' Uj 012
Ash
Sharqiyah, Saudi Arabia
Found:
31 Jan 2012
Mass:
122.78 g
Lunar meteorite (feldspathic breccia)
History:
Found by Edwin Gnos, Beda Hofmann, Khalid al Wagdani,
Ayman Majoub, Abdulaziz
Solami, Siddiq Habibullah,
Maruan Al Bokari during
a search for meteorites on January 31, 2012.
Physical
characteristics: Medium gray stone with a
total mass of 122.78 g. The wind-ablated meteorite consists of two fitting
fragments, with masses of 104.5 and 18.27 g, respectively. Fusion crust is
absent. Contains black, white and red mineral and lithic clasts (up to 6
mm) embedded in a very fine-grained matrix. Vesicles are abundant. Some
vesicles and thin cracks are filled with terrestrial mineral assemblages.
Petrography:
(B. Hofmann NMBE; M. Mészáros NMBE/Bern)
Clast-rich impact-melt breccia, consisting of partly resorbed mineral
clasts (up to 1 mm) and subrounded/rounded lithic clasts (up to 6.8 mm) set
in a very fine-grained, well-crystallized impact-melt matrix. Most common
mineral clasts are plagioclase with minor pyroxene and olivine. The lithic
clast population is dominated by anorthositic breccias. Rare clasts of
igneous rocks and a single basalt clast were observed. Vesicles (up to 3.0
mm diameter) are abundant. Shock features (polycrystalline grains,
mosaicism, recrystallization) were observed in pyroxenes, olivine and
plagioclase. Trace mineral phases are troilite, FeNi-metal,
spinel (pleonast), SiO2 and
terrestrial alteration products (carbonates, celestine, Fe-hydroxides).
Geochemistry:
(N. Greber, M. Mészáros,
Bern) Mineral composition:
feldspar (n=46): An93.4-97.7 Or0.0-1.6; olivine
(n=7): Fa28.4-35.3, Fe/Mn=95.7; orthopyroxene (n=1): Wo3.6
Fs25.2, Fe/Mn=52.8; clinopyroxene (n=10): Wo5.1-40.6
Fs12.8-36.9, Fe/Mn=89.9. Bulk analysis (ICP/ICPMS): Al2O3=28.9
wt%, FeO=5.0 wt%, Sc=8 ppm, Sm=1.2 ppm, Th=0.5 ppm. Oxygen isotopes: (R.
Greenwood, OU): ?18O=5.46 permil, ?17O=2.86 permil
?17O=0.018 permil.
Classification:
Lunar feldspathic impact-melt breccia.
Specimens:
Type material (25.1 g) and 3 polished thin sections at MHNGE, main mass at SGS.
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