Meteoritical Bulletin, No. 107
Northwest Africa 11962
History: In 2013, the NHMV
acquired a single stone weighing 85.8 g from a Moroccan dealer.
Physical characteristics: The
specimen is a flat and rounded individual with regmaglypts exhibiting a
black shiny surface with in places dull brownish areas. A cut and polished
face (3 cm2) reveals two different lithologies comprising a
fine-grained, dark-gray matrix with mainly submillimeter-sized light clasts
and a black compact area (1 × 0.5 cm) of impact melt.
Petrography: (F. Brandstätter, NHMV,
and A. Bechtold, UVien)
Clast-rich breccia containing fine-grained lithic and mineral clasts,
brownish vesicular glass, and brownish to orange glass spherules. In
places, the glass exhibits a flow-banded texture with dark-grey to black
schlieren. Lithic clasts include basalts, gabbroic lithologies,
breccia-within-breccia clasts and granophyric intergrowths of K-feldspar
and silica. Mineral clasts include ortho- and clinopyroxenes (some showing
exsolution lamellae), olivine, plagioclase (mostly anorthitic),
silica, spinel (chromite, ulvöspinel), ilmenite,
zircon, troilite and Fe,Ni metal.
Geochemistry: Olivine Fa38.0±13.5
(N = 40), plagioclase An88.2±11.2Or0.6±0.5 (N = 37),
orthopyroxene Fs14.3±0.4Wo1.3±1.3 (N = 63),
clinopyroxene Fs30.8±9.1Wo23.4±13.5 (N = 43),
K-feldspar (An4.5±1.0Or73.9±6.4, (N = 11) BaO = 1.4-3.4 wt%), exsolved
pyroxene: orthopyroxene host Fs65.5±4.8Wo4.0±1.3 (N =
19) with augite exsolution lamellae Fs33.0±2.3Wo41.6±2.3
(N = 20). The oxygen isotope composition (R. Greenwood, OU) is consistent with a lunar
origin (δ17O = 3.14 per mil, δ18O = 6.03
per mil, Δ17O = 0.01 per mil).
regolith breccia. Moderate weathering.
Specimens: A mass of 80.8 g
and two thin sections are on deposit at NHMV.