Lunar Meteorite: Northwest Africa 11182

A slice of Northwest Africa 11182. Photo credit: Ruben Garcia
Two sides of NWA 11182 (3.6-g slice): Photo credit: Mike Miller
Two sides of another slice of Northwest Africa 11182.  The light-colored, speckled  clast on the left (10.0% FeO; gabbro?) is more mafic than the darker glassy matrix on the right (3.7% FeO). Thanks to Ruben Garcia for the sample. Photo credit: Randy Korotev
Lab sample of Northwest Africa 11182. Thanks to Carl Agee for the sample. Photo credit: Randy Korotev
from The Meteoritical Bulletin, No. 106

Northwest Africa 11182 (NWA 11182)

(Northwestern Africa)
Purchased: 2017
Mass: 60 g (1 piece)

Lunar Meteorite (feldspathic breccia)

History: Purchased by Ruben Garcia from Said Haddany in Tucson, 2017.

Physical characteristics: Single stone, no fusion crust. A saw cut reveals a fragmental breccia with numerous white feldspathic clasts and fine-grained lithic fragments, set in a dark-gray ground mass.

Petrography: (C. Agee, UNM) This meteorite consists of primarily feldspathic clasts, microgabbro clasts, and shock melt, some containing vesicles.

Geochemistry: (C. Agee and B. Ha, UNM) pigeonite Fs28.9±1.6Wo11.8±7.0, Fe/Mn=56±3, n=2; high Ca pyroxene Fs22.7±11.7Wo28.6±5.9, Fe/Mn=52±2, n=2; two olivine grains were found: Fa16.9 and Fa34.6 with Fe/Mn=91 and 98 respectively; plagioclase An92.9±3.2Ab6.8±3.2Or0.3±0.1, n=4.

Classification: Lunar feldspathic breccia.

Specimens: 12 g plus a probe mount on deposit at UNM, Ruben Garcia holds the main mass.

Rare earth element (REE) concentrations in 8 subsamples of NWA 11182.

Randy Says…

The specked white clast is richer in REE as well as more mafic that the matrix.  This is 1 of only 5 lunar meteorites that I know to have a significant negative cerium (Ce) anomaly. All are from Northwest Africa (other 4: NWA 10318, NWA 10495, NWA 11223/11809, and Tichiya). Both the matrix and the clast have Ce anomalies, but the magnitude of the anomalies varies considerably. Pr and Nd values calculated by interpolation between La and Sm. Dy, Ho, Er, and Tm values interpolated between Tb and Yb. The Gd value is the mean of the La-Sm extrapolation, the Sm-Tb interpolation, and the Yb-Tb extrapolation.

More Information

Meteoritical Bulletin Database

NWA 11182

References

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