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Lunar Meteorite: Northwest Africa (NWA) 2995, 2996 (provisional name), 3190, 4503, 5151 (provisional name), 5152 (provisional name), 5153 (provisional name), 5207 (provisional name), & other unnamed stones.Algeria |
We do not know with certainty that all these stones are paired, but they are
all compositionally similar
to each other and together different from other lunar meteorites.
Compositionally, they are most
similar to QUE 94281 & Yamato 981031. (See
plots at the bottom of this
page.)
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See photos of NWA 2996 | NWA
3190 | NWA
4503 | others
from The
Meteoritical Bulletin, no. 90, Meteoritics & Planetary Science
41, 1383-1418 (2006)Northwest Africa 2995AlgeriaFound 2005 Achondrite (lunar feldspathic breccia) History: A 538 g, fully crusted and minimally weathered stone was purchased in Morocco by A. Aaronson in November 2005. Petrography and Geochemistry: (T. Bunch and J. Wittke, NAU): The feldspathic fragmental breccia contains many highlands fine-grained lithologies including norite (orthopyroxene, Fs26.4Wo4, FeO/MnO = 66); olivine basalt (olivine, Fa87.2 FeO/MnO = 95; plagioclase, An84.7); subophitic basalt (Ca-pyroxene, Fs25-48Wo37.1-25.9; pigeonite, Fs27.8-31.7Wo15.4-9.3 FeO/MnO = 53; olivine Fa36.3 FeO/MnO = 90; plagioclase, An97); gabbro (olivine Fa34.7 FeO/MnO = 95; pigeonite Fs28.2Wo8.9 FeO/MnO = 67; plagioclase An94); KREEPy-like basalt (plagioclase, Ab50Or17.4; K-feldspar, Ab14.3Or83.6 in addition to silica, phosphate and Fe-rich pyroxenes); troctolite (Fa30.8 FeO/MnO = 94; plagioclase An94.7); granulitic impact melts (Fa31; orthopyroxene, Fs25.2Wo3.4; plagioclase An95); anorthosite (An92.7-96.8); glassy impact melts, coarse-grained mineral fragments, and a 0.350 mm sized grain of meteoritic Ni, Fe metal (Ni = 6.3 Co = 1.0, both wt %). In addition, the assemblage appears to be characterized by large amounts of breccias within breccias: at least 4 generations of brecciation were observed in one cm-sized breccia clast. Numerous shock-induced melt veins are present along large breccia clast margins as well as isolated melt pockets within clasts. Interior weathering grade is very low, all glasses are fresh and no apparent terrestrial alteration veins were noted. Classification: Achondrite (Lunar feldspathic breccia). Specimens: A 21.2 g specimen is on deposit at NAU. Aaronson holds the main mass. |
from The Meteoritical Bulletin, No. 93, Meteoritics & Planetary
Science 43, Axxx-Axxx (2008) Northwest Africa 3190Northwest AfricaFind: 2006 Achondrite (lunar, mingled breccia) History and physical characteristics: A. Aaronson purchased a 40.7 g partially crusted, complete stone in Rissani, Morocco in December 2006. The hand specimen exhibits an abundance of large (between 0.6 and 2.1 mm in dia.) anorthositic clasts. The weathered portion of the crust is pale vermillion to light brown, fresher crust is dark gray to black. Petrography (T. Bunch and J. Wittke, NAU; A. Irving, UWS): This mingled breccia contains anorthositic lithologies that include anorthosite, anorthositic norites, gabbros and troctolites, in addition to variolitic and subophitic basalt clasts, breccia-within-breccia clasts, and an abundance of olivine and plagioclase fragments. Melt and fragmental matrices are heterogeneously distributed. The interior shows very low weathering effects. Mineral compositions and geochemistry: Anorthositic norite orthopyroxene (Fs28.5Wo3.8; FeO/MnO = 65). Olivine gabbro contains olivine (Fa26.2; FeO/MnO = 96), plagioclase (An92.3), subcalcic pyroxene (Fs21.6Wo14.4; FeO/MnO = 48), and ilmenite with MgO = 6.5 wt%. Variolitic basalt has olivine (Fa35.7; FeO/MnO = 103), pigeonite (Fs24.6Wo8.7) and plagioclase (An95.5). Bulk composition (R. Korotev, WUSL): FeO = 9.6 wt.%, Sm = 3.9 ppm, Th = 1.4 ppm, Ir = 6.5 ppb. Classification: Achondrite (lunar, mingled breccia). Probably paired with NWA 2995, based on essentially identical bulk compositions. Type specimen: A total of 8.8 g is on deposit at NAU. The main mass holder is anonymous. |
from The Meteoritical Bulletin, No. 93, Meteoritics & Planetary
Science 43, Axxx-Axxx (2008) Northwest Africa 4503Northwest AfricaFind: 2007 Achondrite (lunar, anorthositic breccia) History and physical characteristics: A 70 g partially crusted stone was purchased in January 2007 by A. Aaronson and sold to a collector in July 2007. The fusion crust is dark to light brown and vermillion in translucent areas. Petrography (T. Bunch, J. Wittke, NAU; A. Irving, UWS): This feldspathic melt breccia is dominated by very fine to medium-grained anorthositic lithologies that are typically enriched in olivine (anorthositic troctolites and gabbros) together with a large fraction of plagioclase, olivine, and exsolution-textured pyroxene fragments. Shock-melt clasts, K-, Ba-rich glasses, and fayalite-pyroxene-quartz igneous lithologies are also present. One granophyre clast shows a granophyric or micrographic texture of oriented quartz inclusions in alkali feldspar surrounded by shock-melted plagioclase. Most of the matrix is glassy and vesicular with included mineral fragments. Weathering effects are minimal. Mineral compositions and geochemistry: Gabbro: olivine (Fa34.8; FeO/MnO = 88), augite (Fs14.6Wo41.8; FeO/MnO = 42), plagioclase (An97.6), chromite (cr# = 74). Troctolite: olivine (Fa27.9; FeO/MnO = 83). Norite: orthopyroxene (Fs24.8Wo2.5; FeO/MnO = 55), augite (Fs20.4Wo38.9). Basaltic pyroxene fragments, host = Fs46.9Wo2.4, exsolution lamellae = Fs19.8Wo43.4. Granophyre K-feldspar (Or72Ab18.3). Classification: Achondrite (lunar, anorthositic breccia). Type specimen: A total of 14 g is on deposit at NAU. The main mass holder is anonymous. |
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