Lunar Meteorite: Northwest Africa 12909
from The Meteoritical Bulletin, No. 108
Northwest Africa 12909 (NWA 12909)
Lunar meteorite (feldspathic breccia)
History: Purchased by Zuokai Ke in Chenzhou, China, in May 2019 from Moroccan meteorite dealer.
Physical characteristics: Single stone, desert weathered exterior, sawcuts reveal a fragmental breccia with many white, feldspathic clasts set in a dark-gray groundmass.
Petrography: (X. Gu, CSU-China; C. Agee, UNM) This meteorite is composed of anorthite (55%), olivine (23%), augite (15%), orthopyroxene (6%), with ubiquitous minor kamacite, troilite, ulvospinel, ilmenite, Cr-spinel, silica, schreibersite and pentlandite. Brecciated clasts sizes range from several micrometers to 1 mm.
Geochemistry: (X. Gu, CSU-China) Olivine Fa30.4±12.5, n=26; low-Ca pyroxene Fs22.1±10.3Wo3.5±0.8, Fe/Mn=63±8, n=8); augite Fs26.9±11.0Wo22.6±14.1, n=17, plagioclase An97.3±1.9Or0.2±0.3Ab2.6±1.9, n=11. (C. Agee, UNM) Olivine Fa30.0±10.9, Fe/Mn=88±8, n=6; pigeonite Fs28.9±6.0Wo13.2±5.8, Fe/Mn=53±9, n=3; augite Fs20.0±14.9Wo39.2±7.3, Fe/Mn=42±2, n=3, plagioclase An96.3±0.6Or0.2±0.1Ab3.5±0.6, n=3.
Classification: Lunar feldspathic breccia
Specimens: 23.2 g including a probe mount on deposit at UNM, Zuokai Ke holds the main mass.
I have not studied Northwest Africa 12909. Modally, it appears to be a brecciated anorthositic troctolite, but one less forsteritic than the NWA 5744 clan.