Meteoritical Bulletin, No. 106
Rabt Sbayta 007
Rio de Oro, Western Sahara
Meteorite (feldspathic breccia)
History: Purportedly found NE of Bir Anzarane
and purchased by Ben Hoefnagels in February 2017 from a dealer in
Physical characteristics: A single
elongate stone (4432 g) exhibiting whitish mineral and lithic clasts in a
medium gray, very fine-grained matrix.
Petrography: (A. Irving and
S. Kuehner, UWS) Breccia composed
of numerous mineral clasts plus some lithic clasts (themselves breccias) in
a finer grained matrix. Minerals include anorthite, olivine, orthopyroxene,
pigeonite, subcalcic augite, ilmenite, chromite, troilite and taenite.
Geochemistry: Olivine (Fa11.0-33.3,
FeO/MnO = 71-101, N = 6), orthopyroxene (Fs18.2-19.4Wo4.6-4.1,
FeO/MnO = 51-56, N = 2), pigeonite (Fs31.2Wo7.3; Fs48.6Wo5.5;
FeO/MnO = 58-61), subcalcic augite (Fs51.7-59.5Wo27.0-29.3,
FeO/MnO = 67-72, N = 2), plagioclase (An93.0-95.7Or1.0,
N = 2). Bulk composition (R. Korotev, WUSL)
INAA of subsamples gave the following mean abundances (in wt.%) FeO 4.9, Na2O 0.35; (in ppm)
Sc 9.3, Ni 140, La 3.8, Sm 1.83, Eu 0.83, Yb 1.4, Lu 0.20, Hf 1.3, Th 0.63.
(feldspathic breccia). Although this lunar specimen was found in the same
dense collection area as the Rabt Sbayta 002, Rabt
Sbayta 004, Rabt Sbayta 005 and Rabt Sbayta 006 stones (but at a
different location from Gataa Sfar),
it differs from those stones in both petrologic and bulk compositional
characteristics and thus is not paired with them (nor with Rabt Sbayta 008).
Specimens: 35.1 g including
a polished slice at UWB;
remainder with Mr. B. Hoefnagels.