The identification of lunar materials and their correct conservation is a guarantee of scientific research. Numerous lunar samples have arrived at the laboratory for identification and analysis, contributing to the knowledge of lunar sciences.
Thanks to these lunar samples and many others, it has been possible to carry out numerous investigations that have led to thousands of photomicrographs, dozens of analysis reports and a wide arsenal of research, archive and repository data.
Northwest Africa 4734
Rissani, Morocco
Find: October 2006
Achondrite (lunar)
History: Two pieces were purchased from nomads in Erfoud, Morocco, in October 2006 and February 2007.
Physical characteristics: A. Habibi purchased two pieces with a total mass of 477 g in Rissani, Morocco; several other pieces of the same stone totaling 895 g are with Ait Elkaid in Rissani, Morocco. Dull black/brown fusion crust is nearly complete and inside slightly tarnished where absent. It is a gray, coarse-grained, pristine magmatic rock consisting of millimeter-sized phenocrysts of mainly pyroxene and plagioclase.
Petrography: (A. Jambon, O. Boudouma, and D. Badia, UPVI). The texture is best described as shergottite-like. Pyroxene grains are highly fractured while plagioclase laths, partly transformed to maskelynite, are only affected by a small number of fractures. Silica and silica-feldspar glass are minor components. A few patches of impact melt are also observed. Ilmenite, baddeleyite, zirconolite, tranquilityite, pyrrhotite, and metal. Fayalite associated with silica probably results from the dissociation of iron rich pyroxene. Modal mineralogy (vol%): Cpx 50, plagioclase + K-feldspar 32, silica + glass 7.5, opaques (ilmenite, Ti-magnetite, pyrrhotite) + fayalite 7, voids + fractures 3.
Geochemistry: Mineralogy by EMP and SEM. (Trace and major element analyses ICP-MS and ICP-AES, J.-A. Barrat, UBO). Pyroxene grains are complexly zoned (En65Fs21Wo13 to En2Fs83Wo15; FeO/MnO = 78 [average]). A few compositions correspond to pyroxferroite. Plagioclase is normally zoned from An75-91 (average An89) with minor olivine (Fa80-95). Chondrite normalized REE pattern with an enrichment of 53 (La) to 40 (Yb). Trace element pattern with negative anomalies of Sr and Eu. Interstitial glass is high in silica (75 wt%) and contains microcrysts of K-feldspar with a significant celsian component. The chemistry and major and trace elements are identical to NWA 032-479-773 and LAP 02205-02224-02226-02436- 03632. The texture is very similar to that of the LAP specimens. The very low abundance of olivine and the relative abundance of silica in NWA 4734 are the main differences beside the grain size and the slightly different composition of the major phases.
Classification: Achondrite (lunar); extensive shock.
Type specimens: A total of 20 g of sample and one polished section is on deposit at UPVI. Mbarek Ait Elkaid holds the main masses.
Submitted by: A. Jambon, UPVI. The description of NWA 4734 was submitted as a monzogabbro, but the Nomenclature Committee was not convinced by the materials submitted that this was a correct sub-classification for this sample.
Northwest Africa 11788 (NWA 11788)
Mali
Purchased: 2017
Classification: Lunar meteorite (feldspathic breccia)
History: Purchased in Mali by Dustin Dickens from anonymous meteorite hunter.
Physical characteristics: Many dark visually identical appearing pieces, with masses ranging from ~2 kg to many sub-g fragments, showing no fusion crust. Saw cut reveals a finely fragmental breccia with white feldspathic clasts set in a dark gray ground mass with metal flecks and minor vesiculation appearing throughout.
Petrography: (C. Agee, UNM) This meteorite is a breccia of fragmental pyroxene, olivine, plagioclase grains. There are domains that are fine-grained and cataclastic with shock melt and vesicles.
Geochemistry: (C. Agee, UNM) olivine Fa: 31.2±9.4, Fe/Mn=95±7, n=12; clinopyroxene Fs36.0±10.0Wo22.2±8.8, Fe/Mn=60±5, n=12; plagioclase An93.0±1.8, n=7; Shock melt (20 _m defocused electron beam, proxy for bulk meteorite composition): SiO2=43.2±1.7, TiO2=0.46±0.20, Al2O3=24.2±3.6, Cr2O3=0.23±0.08, MgO=7.8±1.4, FeO=8.0±3.2, MnO=0.10±0.05, CaO=14.2±1.4, Na2O=0.35±0.23, K2O=0.08±0.05 (all wt%), n=4.
Classification: Lunar feldspathic breccia
Specimens: 28.9 g including a probe mount on deposit at UNM, Dustin Dickens holds the main mass.
Northwest Africa 8599 (NWA 8599)
(Northwest Africa)
Purchased: 2014 Jun
Classification: Lunar meteorite
History: Purchased by F. Kuntz in June 2014 from a dealer in Zagora, Morocco.
Physical characteristics: Smooth-surfaced, fine grained, greenish-gray stone (36.5 g) with cross-cutting black veins.
Petrography: (A. Irving and S. Kuehner, UWS) Granuloblastic texture with larger grains of anorthite and very small grains of olivine, low-Ca pyroxene, high-Ca pyroxene, Al-bearing chromite, troilite and taenite.
Geochemistry: Olivine (Fa 23.3-23.5, FeO/MnO = 81-83), low-Ca pyroxene (Fs18.9-19.6Wo5.2-4.7; FeO/MnO = 53-58), high-Ca pyroxene (Fs9.8Wo40.6, FeO/MnO = 59), plagioclase (An97.0-97.1Or0.1). Bulk composition (R. Korotev, WUSL) INAA of subsamples gave the following mean abundances (in wt.%) FeO 5.4, Na2O 0.23; (in ppm) Sc 7.1, Ni 140, La 0.71, Sm 0.37, Eu 0.55, Yb 0.34, Lu 0.05, Hf 0.23, Th 0.08.
Classification: Lunar (troctolitic granulitic breccia). On the basis of essentially identical texture, mineralogy and bulk composition, this specimen is paired with NWA 5744.
Specimens: 7.47 g including one polished slice at PSF; main mass with Kuntz.
Northwest Africa 13859 (NWA 13859)
Northwest Africa
Purchased: 2021 Mar
Classification: Lunar meteorite (feldspathic breccia)
History: The meteorite was purchased by Said Yousfi from a dealer in Temara, Morocco. The largest second largest 356 g fragment was subsequently acquired by Luca Cableri. One sample was analyzed by Ansgar Greshake at MNB and a second sample by Paul Carpenter at WUSL.
Physical characteristics: Several dark grayish fragments without fusion crust. The largest ones weighing 694 g, 356 g, 283 g, 283 g, and 99 g, respectively, without fusion crust.
Petrography: Feldspathic breccia composed of mineral clasts and sparse troctolitic lithic clasts set in fine grained, partly glassy matrix. Minerals are predominantly plagioclase and olivine suggesting presence of abundant troctolitic material throughout the meteorite; pyroxenes are rare. Accessory phases are: FeS, ilmenite, Ti-bearing chromite, and secondary barite and calcite.
Geochemistry: (A. Greshake, MNB) zoned olivine: Fa20.8±6.4 (Fa14.6-30.9, FeO/MnO=83±8, n=13); homogeneous olivine: Fa17.7±0.1, FeO/MnO=84±10, n=4; plagioclase: An96.6±0.8 (An95.3-97.6, n=6); (P. Carpenter, WUSL) olivine: Fa19.3-57.4, FeO=82-106, n=8; low-Ca pyroxene: Fs38.2Wo2.1, FeO/MnO=64, n=1); pigeonite: Fs17.7-24.2Wo7.4-15.0, FeO/MnO=42-54, n=3; augite: Fs16.9Wo39.4, FeO/MnO=45, n=1; plagioclase: An94.4-96.6Ab3.4-5.5Or0.0-0.1, n=3.
Classification: Lunar (feldspathic breccia, troctolite-rich).
Specimens: 20.5 g and a polished thin section are at MNB; 1 g and a polished mount are at UWB; main mass with Said Yousfi.
Northwest Africa 8181 (NWA 8181)
Morocco
Purchased: 2013 Jun
Classification: Lunar meteorite (feldspathic breccia)
History: Purchased by Fabien Kuntz in June 2013 from a Moroccan dealer at the Ensisheim Show.
Petrography: (A. Irving and S. Kuehner, UWS) Very fine grained breccia composed of small mineral fragments and some very small metal grains irregularly distributed in a partly glassy and vesicular matrix. Minerals are olivine, orthopyroxene, pigeonite, subcalcic augite, anorthite, rutile, kamacite and minor barite.
Geochemistry: Olivine (Fa26.8-27.6; FeO/MnO = 94-99), orthopyroxene (Fs24.0-27.3Wo4.4-2.5; FeO/MnO = 53-60), subcalcic augite (Fs13.4Wo36.0; FeO/MnO = 47), ferropigeonite (Fs58.5Wo7.8; FeO/MnO = 64). Bulk composition (R. Korotev, WUSL) INAA of subsamples gave the following mean abundances (in wt.%) FeO 6.4, Na2O 0.53; (in ppm) Sc10.0, Ni 530, La 16.5, Sm 7.35, Eu 1.54, Yb 4.82, Lu 0.671, Hf 5.6, Th 2.3.
Classification: Lunar (feldspathic vitric fragmental breccia). The distinctive texture and bulk composition of this specimen indicates that it is paired with NWA 4936, NWA 5406 and other stones from the Siksou Mountain area in southern Morocco.
Specimens: A 3.7 g specimen with one polished surface is at UWB. The main mass is held by Kuntz.
Dar al Gani 400
Libya
Found 1998 March 10
Lunar meteorite (anorthositic breccia)
A 1.425 kg stone was found in Dar al Gani in the Libyan Sahara. Classification and description (J. Zipfel, MPI): the meteorite is partly covered with a brownish fusion crust; fresh surfaces are gray to dark gray; matrix is well consolidated; clasts include subophitic and fine-grained to microporphyritic impact-melt breccias, granulitic fragments, intergranularly recrystallized anorthosites, and mineral fragments; chemical and O isotope composition is characteristic of lunar highland meteorites (Zipfel et al., 1998b); abundances and composition of noble gases do not suggest a pairing with DaG 262 (Scherer et al., 1998b). For further details, see Zipfel et al. (1998b). Type specimen and two polished sections are with the MPI; main mass with finder.
Northwest Africa 14005 (NWA 14005)
Algeria
Find: 2020
Classification: Lunar meteorite (feldspathic breccia)
History: Acquired in 2020 by Jose Garcia from Khaled Zed, who had previously found the sample in Algeria.
Physical characteristics: Single stone, gray in color,covered by desert varnish. It retains a small part of the eroded fusion crust. The interior is composed of light and dark clasts, with visible shock melt veins present throughout the matrix.
Petrography: (Jose Garcia, MCM; D. Sheikh, Cascadia) This specimen is a breccia composed predominantly of sub-angular to sub-rounded anorthitic clasts (up to ~1.5 mm) and isolated mineral fragments of olivine and pyroxene set in a fine-grained matrix that contains interconnected areas of shock melt veins and trace amounts of ilmenite and troilite. Estimated modal abundances: Anorthitic plagioclase (90%), Olivine (3%), Pyroxene (3%), Shock melt veins (3%), Opaques (1%).
Geochemistry: (D. Sheikh, Cascadia) Olivine (Fa33.9±3.5, range Fa30.9-37.8, Fe/Mn=72±4, n=5), Low-Ca Pyroxene (Fs42.1±1.5Wo0.8±0.1, range Fs41.0-43.2Wo0.7-0.8, Fe/Mn=50±4, n=2), Pigeonite (Fs28.7±3.2Wo17.7±2.7, range Fs23.4-35.2Wo14.9-21.9, Fe/Mn=53±5, n=10), Augite (Fs21.0±4.0Wo32.0±4.6, range Fs16.9-24.8Wo27.9-37.0, Fe/Mn=53±6, n=3), Plagioclase (An96.0±0.5, range An94.8-97.0, n=36).
Classification: Lunar (feldspathic breccia).
Specimens: 3.04 g and a thin section at Cascadia; main mass (11.8 g) with Jose Garcia at MCM.
Northwest Africa 10495 (NWA 10495)
Morocco
Find: 2015
Classification: Lunar meteorite (feldspathic breccia)
History: A group of similar stones were found together at an undisclosed location in southern Morocco during 2015.
Physical characteristics: Several grayish brown stones (total weight 15.6 kg) lacking fusion crust, but with a polished external appearance. All exhibit the same overall fine grained texture, with some visible larger whitish clasts within a dark gray matrix.
Petrography: (A. Irving and S. Kuehner, UWS) Relatively fine grained fragmental breccia composed of mineral clasts of anorthite, pigeonite, olivine, augite, Ti-chromite and troilite set in a matrix containing minor secondary barite.
Geochemistry: Olivine (Fa34.8-42.3, FeO/MnO = 86-95, N = 4), pigeonite (Fs29.8-32.4Wo8.8-12.9, FeO/MnO = 47-52, N = 3), augite (Fs20.6Wo35.4, FeO/MnO = 49), plagioclase (An96.4-97.1Or0.1, N = 2). Bulk composition (R. Korotev, WUSL) INAA of subsamples gave the following mean abundances: (in wt.%) FeO 7.0, Na2O 0.30; (in ppm) Sc 17.0, La 1.9, Sm 1.0, Eu 0.67, Yb 1.0, Lu 0.15, Hf 0.6, Th 0.15.
Classification: Lunar (feldspathic breccia).
Specimens: 24.3 g including one stone polished on one side at UWB; the remaining material is held by the anonymous finders.
Northwest Africa 6950 (NWA 6950)
(Northwest Africa)
Purchased: 2011 Aug
Classification: Lunar meteorite (gabbro)
History: Reported to be found near the border between Mali and Algeria in June 2011, and purchased from the finder by Adam Aaronson in August 2011.
Physical characteristics: A single yellowish-green stone (1649 g, broken into 8 pieces) with partial fusion crust. Thin black shock veins are visible in the interior.
Petrography: (A. Irving and S. Kuehner, UWS) Relatively coarse grained with a cumulate igneous texture. Aggregate dominated by olivine, low-Ca pyroxene, pigeonite, and subcalcic augite, with interstitial very calcic plagioclase. Accessory minerals are ilmenite, Ti-chromite, armalcolite, troilite, baddeleyite, taenite and merrillite with rare zirconolite and K-feldspar.
Geochemistry: Olivine (Fa31.9-32.7, Fe/Mn=85-97), low-Ca pyroxene (Fs27.1-28.1Wo4.8-4.5, Fe/Mn=47-55), pigeonite (Fs25.6±0.0Wo9.2-11.1, Fe/Mn=47-52), subcalcic augite (Fs13.9Wo36.9, Fe/Mn=41), plagioclase (An87.9-93.0Or1.1-0.9).
Classification: Achondrite (lunar, gabbro). This specimen is texturally and mineralogically identical to NWA 2977 and the olivine gabbro clasts in NWA 773, NWA 2700, NWA 2727 and NWA 3333, and evidently is paired with those stones.
Specimens: A total of 20.1 g of sample and one polished thin section are on deposit at UWS. The main mass is held by Aaronson.
Northwest Africa 11273 (NWA 11273)
(Northwest Africa)
Purchased: 2017 Apr
Classification: Lunar meteorite (feldspathic breccia)
History: Material excavated from a site near Tindouf, Algeria was purchased by a consortium of collectors (Rob Wesel, Eric Twelker and Jason Phillips) in April 2017 from Moroccan dealers.
Petrography: (A. Irving and S. Kuehner, UWS) Breccia composed of mineral clasts of anorthite, olivine, exsolved pigeonite, pigeonite, augite, chromite, Ti-Cr-Fe spinel, kamacite, taenite and troilite in a finer grained matrix containing small vesicles and minor barite. Rare basalt clasts and glass fragments are also present.
Geochemistry: Olivine (Fa8.7-59.7, FeO/MnO = 89-111, N = 4), pigeonite (Fs28.8Wo11.2, FeO/MnO = 56), clinopyroxene host (Fs15.3Wo40.9, FeO/MnO = 44), orthopyroxene exsolution lamella (Fs34.0Wo2.7, FeO/MnO = 56), augite (Fs16.8Wo41.7, FeO/MnO = 62), plagioclase (An95.9-96.5Or0.2, N = 2).
Classification: Lunar (feldspathic regolith breccia).
Specimens: 37 g including one polished slice at UWB; remaining pieces shared by Mr. R. Wesel, Mr. E. Twelker and Mr. J. Phillips.
Northwest Africa 11228 (NWA 11228)
(Northwest Africa)
Purchased: 20 Mar 2017
Classification: Lunar meteorite (feldspathic breccia)
History: Purchased by Dustin Dickens, March 20, 2017, from Mohamed Maulud.
Physical characteristics: Many irregular shaped fragments, dark sand-blasted exterior, no fusion crust.
Petrography: (C. Agee, UNM) This meteorite is a fragmental breccia with pyroxene, plagioclase, and olivine grains set in fine grained groundmass. Scatttered micro-gabbro fragments were also observed. Ubiquitous, fine grained, accessory Fe-metal and sulfide are present. Minor amount of shock melt was observed in the microprobe section. All pyroxene grains probed were pigeonite, no augite was detected.
Geochemistry: (C. Agee and B. Ha, UNM) Olivine Fa40.2±13.6, Fe/Mn=93±9, n=10; pigeonite Fs36.1±7.9Wo11.6±3.5, Fe/Mn=57±6, n=11; plagioclase An94.4±1.1Ab5.0±1.0Or0.6±0.2, n=5; shock melt (proxy for bulk composition) Al2O3=26±1, TiO2=0.14±0.09, MgO=12±6, FeO=3±2 (all wt%), n=2.
Classification: Lunar (feldspathic breccia)
Specimens: 20.3 g including a probe mount on deposit at UNM, Dustin Dickens holds the main mass.
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