Lunar Meteorite: Northwest Africa 11457

Photo of a thin section of Northwest Africa 11457. Photo credit: Ann-Kathrin Kraemer and Addi Bischoff

from The Meteoritical Bulletin, No. 106

Northwest Africa 11457 (NWA 11457)

Found: 2016
Mass: 273 g (7 pieces)

Lunar meteorite (feldspathic breccia)

History: Seven pieces with a total mass of 273 g were purchased form a Moroccan dealer in Ouazazate, Morocco May 2016. The sample may have been found in Algeria and brought by nomads to a dealer in Zwirate in the north of Mauritania.

Physical characteristics: The susceptibility values (J. Gattacceca, CEREGE) for the four largest samples are as follows: log χ (× 10-9 m3/kg) = 3.31 (117.7g sample); log χ (× 10-9 m3/kg) = 3.56 (88.64 g sample); log χ (× 10-9 m3/kg) = 3.25 (39.91 g sample); log χ (× 10-9 m3/kg) = 3.25 (15.34 g sample).

Petrography: (A.-K. Kraemer and A. Bischoff, IfP) Breccia composed of angular anorthite-rich lithic and mineral fragments embedded in a fine-grained clastic matrix. Observed minerals include anorthite, olivine, low-Ca pyroxene, Ca-rich pyroxene, silica polymorph, Al-Ti-chromite, kamacite, ilmenite, troilite, pendlandite and schreibersite. Calcite veins indicate moderate degree of weathering.

Geochemistry: Mineral compositions and geochemistry: Olivine (mean: Fa48.2, Fe/Mn = 101; N = 199), low-Ca pyroxene (mean Fs35.4Wo12.4, Fe/Mn = 62, 22,9 N = 199), Ca-rich pyroxene (mean: Fs30.7Wo35.2; Fe/Mn = 69; N = 73), anorthite (mean An92.7Or0.3, N = 201).

Classification: Lunar (feldspathic breccia).

Specimens: 22.9 g and thin sections. Main mass with Ben Hoefnagels.

Randy Says…

I have not studied 11457. An92.7 is unusually low for a feldspathic breccia.

More Information

Meteoritical Bulletin Database

NWA 11457