Lunar Meteorite: Northwest Africa 8022 and 10082

paired stones

Northwest Africa 8022. Photo credit: Adam Aaronson
Sawn face of NWA 8022. Image credit: I don’t know where and how I got this image. Let me know if it is yours.
Lab sample of NWA 8022. Photo credit: Randy Korotev
Lab sample of NWA 10082. Photo credit: Randy Korotev

from The Meteoritical Bulletin, No. 102

Northwest Africa 8022 (NWA 8022)

(Northwest Africa)
Purchased: 2013 May
Mass: 1226 g (1 piece)

Classification: Lunar meteorite (feldspathic breccia)

History: Purchased in Temara, Morocco by Adam Aaronson in April 2013.

Physical characteristics: A single, fine grained stone (1226 g) with patches of remnant, brown fusion crust.

Petrography: (A. Irving and S. Kuehner, UWS) Highly recrystallized fragmental feldspathic breccia containing some larger anorthite grains (up to 2 mm), but mostly composed of extremely fine grained (~10 microns) anorthite, pigeonite, olivine, ilmenite, Cr-ulvöspinel, fayalite, kamacite, pentlandite and rare awaruite.

Geochemistry: Anorthite (An95.9Or0.3), pigeonite (Fs20.6-22.2Wo21.5-10.0; FeO/MnO = 50-58), olivine (Fa31.5-31.7; FeO/MnO = 93-101). 

Bulk composition (R. Korotev, WUSL): INAA of subsamples gave mean abundances of FeO 3.7 wt.%, and (in ppm) Sc 5, La 2.7, Sm 1.2, Eu 0.98, Yb 1.1, Th 0.7.

Classification: Lunar (feldspathic granulitic breccia).

Specimens: 21.5 g are at UWB. The remainder is with Aaronson.

from The Meteoritical Bulletin, No. 102.

Northwest Africa 10082

(Northwest Africa)
Purchased: 2014 August
Mass: 5.20 g (3 pieces)

Classification: Lunar meteorite (feldspathic breccia)

History: Purchased by Alexandre Debienne in August 2014 from a dealer in Agadir, Morocco.

Petrography: (A. Irving and S. Kuehner, UWS) Very fine grained annealed breccia with granoblastic texture. Minerals are anorthite, olivine, pigeonite, pentlandite, pleonaste and troilite, with minor fayalite and kamacite.

Geochemistry: Olivine (Fa29.2-31.4, FeO/MnO = 103-129, N = 3), pigeonite (Fs21.7-23.0Wo17.2-11.8, FeO/MnO = 55-56, N = 3). 

Bulk composition (R. Korotev, WUSL) INAA of subsamples gave the following mean abundances (in wt.%) FeO 3.5, Na2O 0.46; (in ppm) Sc 5.1, Ni 490, La 2.8, Sm 0.73, Eu 0.96, Yb 1.1, Lu 0.15, Hf 1.0, Th 0.72.

Classification: Lunar (feldspathic granulitic breccia). Paired with NWA 8022 based on distinctive texture and bulk composition.

Specimens: 1.28 g including a polished piece at PSF; main mass with Mr. A. Debienne.

Randy Says…

I wish I had a whole-rock photo of NWA 10082 to compare with that of NWA 8022. I admit that my lab samples do not look all that similar, but they are compositionally identical and together different from other NWA lunar meteorites (highly feldspathic, but unusually rich in Na and Eu). Both are granulitic breccias. The purchase locations, however, are ~460 km apart.

More Information

Meteoritical Bulletin Database

NWA 8022 | 10082

References

Korotev R. L. and Irving A. J. (2014) Keeping up with the lunar meteorites  2014. 45th Lunar and Planetary Science Conference, abstract no. 1405.

Korotev R. L. and Irving A. J. (2016) Not quite keeping up with the lunar meteorites – 2016. 47th Lunar and Planetary Science Conference, abstract no. 1358.

Korotev R. L. and Irving A. J. (2021) Lunar meteorites from northern Africa. Meteoritics & Planetary Science, 206–240. 

Kuehner S. M., Irving A. J., and Korotev R. L. (2014) Petrology and composition of lunar felsic granulitic breccia Northwest Africa 8022 and occurrence of forsterite in lunar breccia NWA 8001. 45th Lunar and Planetary Science Conference, abstract no. 2495.