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| Northwest Africa 10989 | |||||||||||||||||||||||||||||||
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| Basic information | Name: Northwest Africa 10989 This is an OFFICIAL meteorite name. Abbreviation: NWA 10989 Observed fall: No Year found: 2015 Country: (Northwest Africa) Mass:  14.4 g | ||||||||||||||||||||||||||||||
| Classification history: |
This is 1 of 103 approved meteorites classified as Lunar. [show all] Search for other: Lunar meteorites | ||||||||||||||||||||||||||||||
| Comments: | Approved 17 Dec 2016 | ||||||||||||||||||||||||||||||
| Writeup |
Writeup from MB 105:
Northwest Africa 10989 (NWA 10989) (Northwest Africa) Purchased: 2015 Classification: Lunar meteorite History: This stone was one of a group found in northwest Africa, near to the Morocco/Algeria border; exact date and weights of other stones is unknown. Purchased in 2015 from a Moroccan Dealer in Morocco. Physical characteristics: The total mass of the single stone was 14.4 g, and is dark brown in color with a dark brown/black fusion crust. Petrography: H. Ashcroft, M. Anand, OU. A fragmental breccia containing a variety of mineral (up to 1 mm) and lithic (up to 1 × 3 mm) fragments in a dark matrix composed of finer-grained crystals and a dark, vesicular glass. Both basaltic and feldspathic fragments are present in roughly equal proportions. The breccia has a seriate fabric and the proportion of glass and crystals in the matrix varies throughout the sample. Some crystals exhibit evidence for shock and alteration (offset pyroxene lamellae, recrystallized and maskelynitised plagioclase). Minor secondary calcite veins and barite are seen throughout the sample. Minerals are Olivine (forsteritic and fayalitic), Pyroxene (Orthopyroxene, Pigeonite, Augite), Anorthite and trace amounts of ilmenite, chromite, kamacite, schreibersite, apatite, merrilite, silica. Geochemistry: Feldspar crystals are anorthitic and vary between An80-90, with an average of An94 (N = 184). Some feldspars are recrystallized, and others have been maskelynitised. A continuum of pyroxene compositions (pigeonite to augite) are observed with a range in Fs15-64, and Wo5-43. Four main clusters in olivine composition are observed with Fa37, Fa51 and Fa70. Some Fayalite (Fa90) is also observed. One mafic clast contains orthopyroxene (Wo3En75Fs22), Olivine, (Fa75) and anorthite (An95). One hedenbergite-fayalite-silica symplectite is observed. The oxygen isotopes (R. Greenwood and I. Franchi, OU) are consistent with a lunar origin with δ17O 3.42 ‰, δ18O 6.51 ‰, Δ17O 0.03 ‰. Average FeO/MnO for Olivine is 105, and Pyroxene is 66. Classification: Lunar (mixed fragmental breccia) Specimens: Main mass resides with G. Ensor. The type specimen (3.4 g) is deposited in the OU meteorite collection. | ||||||||||||||||||||||||||||||
| Data from: MB105 Table 0 Line 0: |
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| Plots: | O isotopes: | ||||||||||||||||||||||||||||||
| Institutions and collections |
OU: Planetary and Space Sciences
Department of Physical Sciences
The Open University
Walton Hall
Milton Keynes
MK7 6AA
United Kingdom, United Kingdom (institutional address; updated 8 Dec 2011) |
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| References: | Published in Meteoritical Bulletin, no. 105, MAPS 52, 2411, September 2017. http://onlinelibrary.wiley.com/doi/10.1111/maps.12944/full
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| Geography: |
Statistics: This is 1 of 9305 approved meteorites from (Northwest Africa) (plus 1873 unapproved names) | ||||||||||||||||||||||||||||||