Lunar Meteorite: Northwest 14137, 14526, and 14992

from The Meteoritical Bulletin, No. 110

Northwest Africa 14137 (NWA 14137)

(Northwestern Africa)
Find: 2021
Mass: 77 g (1 piece)

Lunar meteorite (basalt)

History: Reportedly found in 2021 and purchased by Doug Chenin in 2021 from a meteorite dealer in Mauritania.

Physical characteristics: Single stone, with smooth to irregular exterior surface, no fusion crust present, and numerous vesicles pits visible in hand sample. Polished saw cuts reveal a fine-grained mix of dark-gray and light-brown grains, many dark shock melt pockets present. Unbrecciated.

Petrography: (C. Agee, UNM) Backscattered electron images shown igneous-zoned olivines and pyroxenes. Maskelynite makes up approximately 25% of the modal mineralogy, ubiquitous acicular ilmenite ~5%, minor ulvospinel, troilite, chromite and silica observed. Quench melt pockets are present throughout.

Geochemistry: (A. Ross and C. Agee, UNM) Olivine Fa_57.7±21.1, Fe/Mn=99±4, n=9; clinopyroxene Fs_46.1±19.2Wo_25.1±5.6, Fe/Mn=64±12, n=12;, maskelynite An_88.5±0.8Ab_11.0±0.8, n=6. Quench melt SiO₂=43.7±0.7, TiO₂=4.1±0.3, Cr₂O₃=0.24±0.08, Al₂O₃=10.1±1.2, MgO=5.9±1.6, FeO=22.2±1.0, MnO=0.28±0.02, CaO=10.7±0.5, Na₂O=0.42±0.16, K₂O=0.12±0.05 (all wt%, 30 μm defocused beam), n=8. Clinopyroxene shows Fe-enrichment trends that are continuous from Mg-augite and Mg-pigeonite to subcalcic-ferroaugite/ferropigeonite.

Classification: Lunar (mare basalt). Based on the TiO₂ content of quench melt this is meteorite transitional between low-Ti and intermediate-Ti mare basalt (Giguere et al. 2000).

Specimens: 15.9 g including a probe mount on deposit at UNM, DChenin holds the main mass.

from The Meteoritical Bulletin, No. 110

Northwest Africa 14526 (NWA 14526)

(Northwestern Africa)
Purchased: 2021
Mass: 505 g (1 piece)

Lunar meteorite (basalt)

History: Found in northwest Africa, purchased by Luc Labenne from meteorite dealer in 2021.

Physical characteristics: Single stone, with smooth to irregular exterior surface, no fusion crust present, and numerous vesicles pits visible in hand sample. Polished saw cuts reveal a fine-grained mix of dark-gray and light-brown grains, many dark shock melt pockets present. Unbrecciated.

Petrography: Single stone with a smooth to irregular exterior surface with indentations resembling large vesicles; patches of sandblasted fusion crust were also observed. Freshly broken surface reveals a fine-grained mix of dark gray and light brown grains, shiny maskelynite patches are present. Unbrecciated.

Geochemistry: (A. Ross and C. Agee, UNM) Olivine Fa_60.6±15.3, Fe/Mn=104±5, n=10; clinopyroxene Fs_36.3±9.3Wo_16.8±7.9, Fe/Mn=60±7, n=19; maskelynite An_85.8±5.6Ab_13.6±5.6, n=6. Quench melt SiO₂=44.4±0.4, TiO₂=2.7±0.2, Cr₂O₃=0.46±0.01, Al₂O₃=8.3±0.7, MgO=10.7±0.6, FeO=24.5±0.8, MnO=0.30±0.02, CaO=8.8±0.3, Na₂O=0.30±0.04, K₂O=0.13±0.04 (all wt%, 30 micron defocused beam), n=4. Clinopyroxene shows Fe-enrichment trends that are continuous from Mg-augite and Mg-pigeonite to subcalcic-ferroaugite.

Classification: Lunar (mare basalt). Based on the TiO₂ content of quench melt this is meteorite is a low-Ti mare basalt (Giguere et al., 2000).

Specimens: 20 g including a probe mount on deposit at UNM, Labenne holds the main mass.

from The Meteoritical Bulletin, No. 111

Northwest Africa 14992 (NWA 14992)

(Northwestern Africa)
Purchased: 2022
Mass: 158 g (1 piece)

Lunar meteorite (basalt)

History: Reportedly found in 2021 and purchased by Ziyao Wang in 2022 from a meteorite dealer in Mauritania.

Physical Characteristics: Single stone with irregular brown exterior surface, no fusion crust present. Fresh broken surface shows a fine-grained mix of gray and light brown grains, with abundant shiny fine grained maskelynite, and some small dark shock melt veins. Unbrecciated.

Petrography: (C. Agee, UNM) Backscatter electron and reflected light microscope images show igneous-zoned olivines and pyroxenes. The modal abundance ratio of olivine to pyroxene is approximately 1:3. Maskelynite makes up approximately 25% of the modal mineralogy. Minor phases include Ti-Cr spinel, Ti-magnetite, ilmenite, troilite, taenite, and kamacite. A prominent shock melt vein was present in the deposit sample microprobe mount.

Geochemistry: (A. Ross and C. Agee, UNM) Olivine Fa_53.7±10.1, Fe/Mn=103±10, n=10; clinopyroxene Fs_40.2±12.4Wo_23.7±7.1, Fe/Mn=64±8, n=20; maskelynite An_88.0±2.1Ab_11.5±1.9, n=7. Quench melt SiO₂=44.0±0.6, TiO₂=2.0±0.1, Cr₂O₃=0.48±0.04, Al₂O₃=10.5±1.8, MgO=8.0±0.7, FeO=20.8±1.3, MnO=0.24±0.03, CaO=10.6±0.4, Na₂O=0.45±0.05, (all wt%, 30 micron defocused beam), n=4. Clinopyroxene shows Fe-enrichment trends that are continuous from Mg-augite and Mg-pigeonite to subcalcic-ferroaugite/ferropigeonite.

Classification: Lunar (mare basalt). Based on the TiO₂ content of quench melt this is meteorite is a low-Ti mare basalt (Giguere et al. 2000).

Specimens: 21 g including a probe mount on deposit at UNM, WangZ holds the main mass.

Randy Says…

I have not studied these meteorites. I am putting them on the same page so that others can compare the descriptions, which I find to be similar. I suspect that NWA 14137 is not related to the others because of the vesicles.

Li and Jiang (2023): “The preliminary [petrographic] results show that NWA 14526 and NWA 14992 probably belong to a pair of low-titanium mare basalts, and they are closely related to NWA 10597.” NWA 10597 is a pair to NWA 4734. I doubt that any of these three meteorites is paired or launch paired with NWA 032/10597, which have distinct fusion crusts (as do their launch pairs, the LAP 02205 clan), while none of the three meteorites of this page have fusion crusts.

More Information

Meteoritical Bulletin Database

NWA 14137 | 14526 | 14992

References

Giguere T. A., Taylor G. J., Hawke B. R., abd Lucey P. G. (2000) The titanium contents of lunar mare basalts. Meteoritics & Planetary Science, 35, 193-200.

Li P. and Jiang Y. (2023) Mineral chemistry of two new mare basalts Northwest Africa (NWA) 14526 and NWA 14992. 86th Annual Meeting of the Meteoritical Society, abstract no. 6249.