Lunar Meteorite: Northwest Africa 13676, 13757, 13908 & 15352
assumed paired stones
from The Meteoritical Bulletin, No. 110 Northwest Africa 13676 (NWA 13676)Algeria Classification: Lunar meteorite (feldspathic breccia) History: Purchased by Didi Baideri in September 2020 from an Algerian dealer and subsequently sold to Ziyao Wang in December 2020. Physical characteristics: A single dark, very fine grained stone (698 g) coated by a shiny patina. Petrography: (A. Irving, UWS and P. Carpenter, WUSL) Fine grained breccia composed of mineral clasts of anorthite, olivine, pigeonite and augite, plus feldspathic lithic clasts (including quench-textured melt clasts), set within a very fine grained, partly vesicular matrix containing kamacitic metal (with variable Fe:Ni) and chromite (with variable Ti content). Geochemistry: Olivine (Fa26.6-42.8, FeO/MnO = 87-105, N = 6), pigeonite (Fs23.4-35.1Wo6.6-10.2, FeO/MnO = 52-64, N = 5; Fs39.7-47.2Wo14.9-16.7,FeO/MnO = 54-58, N = 2), augite (Fs20.8Wo37.4, FeO/MnO = 56), anorthite (An94.8-95.5Or0.3-0.5, N = 3). Classification: Lunar (feldspathic breccia). Specimens: 221.8 g including one polished endcut at UWB; remainder with Mr. Z. Wang. |
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from The Meteoritical Bulletin, No. 110 Northwest Africa 13757 (NWA 13757)Algeria Classification: Lunar meteorite (melt breccia) History: Numerous stones (purportedly found at the same unspecified site in Algeria which produced NWA 13676) were purchased by Darryl Pitt in December 2020 from a dealer in Zagora, Morocco. Physical characteristics: All of the stones (total weight 16974 g) are dark gray and relatively fine grained with an exterior shiny patina. Petrography: (A. Irving, UWS and P. Carpenter, WUSL) Breccia composed of mineral clasts of anorthite, olivine, low-Ca pyroxene, pigeonite and augite plus mafic lithic clasts in a very fine grained matrix containing partially altered kamacite, both high-Ti and low-Ti chromite, and minor secondary barite and celestite. These specimens are richer in mafic components by comparison with typical feldspathic lunar breccias. Mafic lithic clasts include microgabbro, subophitic olivine-bearing mare basalt and quench-textured basalt lithologies. The matrix exhibits some fluidal alignment of elongate mineral clasts and is sparsely microvesicular. Geochemistry: Olivine (Fa26.2-41.1, FeO/MnO = 81-92, N = 5), low-Ca pyroxene (Fs27.8Wo4.4, FeO/MnO = 60), pigeonite (Fs23.9-35.9Wo13.5-18.6, FeO/MnO = 43-52, N = 3), subcalcic augite (Fs43.6Wo32.4, FeO/MnO = 51), augite (Fs11.0Wo38.4, FeO/MnO = 41), anorthite (An93.8-96.6Or0.4-0.1, N = 3). Classification: Lunar (melt breccia). This material has textural, petrologic and mineral chemical features consistent with being paired to the stone classified as NWA 13676, and was procured from the same Algerian source. Specimens: 20.85 g in the form of a polished endcut at UWB; remainder with DPitt. |
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from The Meteoritical Bulletin, No. 110 Northwest Africa 13908 (NWA 13908)(Northwest Africa) Classification: Lunar meteorite (melt breccia) History: Purchased in Agadir, Morocco by Aziz Habibi in December 2020. Physical characteristics: A single dark gray, relatively fine grained stone (1680 g) with an exterior shiny patina. Petrography: (A. Irving, UWS and P. Carpenter, WUSL) Breccia composed of mineral clasts of anorthite, olivine, pigeonite, exsolved pigeonite and augite plus mafic lithic clasts in a very fine grained matrix containing metal (with variable Fe:Ni intermediate between values for kamacite and taenite), chromite and ilmenite. Mafic lithic clasts include microgabbro and quench-textured basalt lithologies. The matrix exhibits some fluidal alignment of elongate mineral clasts and is sparsely microvesicular. Geochemistry: Olivine (Fa24.0-37.5, FeO/MnO = 77-92, N = 5), pigeonite (Fs25.3-41.1Wo8.0-16.6, FeO/MnO = 40-59, N = 4), subcalcic augite (Fs21.1-28.6Wo27.1-32.6, FeO/MnO = 51-53, N = 2), augite (Fs23.3Wo40.9, FeO/MnO = 52), low-Ca pyroxene host (Fs46.0Wo3.2, FeO/MnO = 67), augite exsolution lamella (Fs19.9Wo42.8, FeO/MnO = 58), anorthite (An96.5-97.6Or0.2-0.0, N = 3). Classification: Lunar (melt breccia). This material has textural, petrologic and mineral chemical features consistent with being paired to the stones classified as NWA 13676 and NWA 13757. Specimens: 23.0 g including a polished mount at UWB; remainder with Mr. A. Habibi. |
| from The Meteoritical Bulletin, No. 111 Northwest Africa 15352 (NWA 15352)(Northwest Africa) Classification: Lunar meteorite (feldspathic breccia) History: The 82 stones were bought for the Dedovsk Museum collection (DMUH) from the meteorite dealer Mr. Abdel Aziz Moudani in 2021. Mr. Moudani told in private communication that tens of the meteorite samples of several kilograms in total mass were recovered in 2020 in Algeria near the finding place of the lunar meteorite Northwest Africa 13676. Physical characteristics: The meteorite samples of quasi-ovoid shapes have dark-olive to black surface without a fusion crust. The mass range of the samples is 0.4-1790 g. A total mass of the samples is 4125 g. Petrography: (Lorenz C. A., Vernadadsky) The meteorite is a melt breccia. It is made of rock and mineral fragments set in a melt rock matrix. The largest rock fragments of 1-3 mm in size are clastic breccias, medium- to coarse-grained anorthosites and medium-grained ophitic basalts. Smaller rocks fragments are anorthosite, basalt, melt rock, melt breccia, granulite. The melt rock matrix is the fine- to medium grained aggregate of pyroxene and feldspar. Occasionally it contains vesicles 0.1-3 mm in size, some of which are filled with calcite due to terrestrial weathering. Mineral fragments are pyroxene, feldspar, olivine, accessory spinel, silica, zircon, Fe,Ni metal. Some fractures in the breccia are filled by calcite or barite. Metal is partially replaced by Fe,Ni hydroxides. Geochemistry: Mineral compositions and geochemistry: Anorthosites: feldspar An96.2-99.9 Ab0.1-3.8 (N=5); pyroxene Fs13.0-23.5 Wo3.6-39.6; Fe/Mn=49.4-55.8 (N=3); olivine Fa26.7-30.1; Fe/Mn=63.1-78.5 (Fe/Mn=3); Basalts: pyroxene Fs19.7-46.9Wo4.7-30.2; Fe/Mn=42.1-78.7 (N=20); feldspar An93.5-99.9Ab0.1-5.8 (N=17); olivine: Fa23.2-53.6; Fe/Mn=60.7-114.4 (N=12). Matrix melt: feldspar An95.7Ab4.3; pyroxene En15.2-28.3Wo17.5-20.5 (Fe/Mn=49); olivine Fa35 (Fe/Mn=74); melt rock matrix bulk (wt. %): MgO 6.6; Al2O3 25.3; SiO2 44.7; Ca 15.2; FeO 5.9. Fe,Ni metal contains 6.5-11 wt. % Ni. Classification: Lunar feldspathic breccia, moderate weathered. Specimens: Type specimen of 604.9 g (individuals: 435, 117, 13.2, 12.0 g; endcuts: 14.2, 5.5, 2.1, 1.9 g.; slices: 1.9, 1.5, 0.68) and three polished sections are on deposit in Vernad. DMUH holds the fragment of 102.2 g and endcut of 17.6 g. Anonymous person holds the main mass. |
| Randy Says… I have not studied these 4 meteorites. I suspect that they are paired on the basis of the descriptions. |