from The
Meteoritical Bulletin, No. 94, September 2008. Meteoritics & Planetary
Science 43, 1551–1588 (2008).
Northwest Africa 5207
Morocco
Find: 2007
Achondrite (lunar feldspathic breccia)
History and physical characteristics: A 101 g stone
was purchased in Rissani, Morocco in 2007 by A.
Aaronson. The exterior is dark in color.
Petrography (T. Bunch and J. Wittke, NAU): The
fragmental matrix contains a wide variety of lithic,
glassy, and shocked components that mainly include
plagioclase-olivine orthocumulates, recrystallized
noritic and troctolitic anorthosites, anorthosites,
gabbros and course to fine-grained basalts,
microbreccias, shock-melted lithologies, symplectites
(from pyroxferroite decomposition), very sparse
Apollo-like “green glasses” (A), and irregular-shaped
light to dark green glasses (B), some of which are
vesicular and contain tiny metal-sulfide spherules. The
interior weathering grade is very low.
Mineral/phase chemistry: Orthocumulate olivine,
Fa26.5 (FeO/MnO = 96) and plagioclase, An99.3.
Coarse-grained basalt olivine is Fa30; Ca-pyroxene
core, Fs45.1Wo30.4 and rim, Fs62.7Wo16.8; plagioclase,
An87.7. Fine-grained basalt olivine is Fa56.9 (FeO/MnO
= 93); Ca-pyroxene, Fs28.5Wo34.7; plagioclase, An91.2.
Green glasses (B) in wt %: SiO2 = 43.8; Al2O3 = 18.7;
Cr2O3 = 0.50; TiO2 = 0.78; FeO = 12.5; MgO = 7.0;
CaO = 15.2; K2O = 0.33 and Na2O = 0.58 (N = 17).
Bulk chemistry (R. Korotev, WUSL): Na2O = 0.484
wt %; Sc = 15.52 ppm; Cr = 1065 ppm; FeO = 7.56 wt
%; Co = 26.7 ppm; Ni = 233 ppm; Th = 1.26 ppm and
Ba = 123 ppm.
Classification: Achondrite (lunar, feldspathic
breccia).
Type specimen: A total of 20 g is on deposit at NAU. The main mass holder is anonymous. |
More Information
Meteoritical Bulletin Database
NWA
5207
References
Korotev R. L., Zeigler R. A., Irving A. J.,
and Bunch T. E. (2009) Keeping
up with the Lunar Meteorites — 2009 (abstract).
In Lunar and Planetary Science XL, abstract no.
1137, 40th Lunar and Planetary Science Conference, Houston.
Korotev R. L, Zeigler R. A., Jolliff B. L.,
Irving A. J., and Bunch T. E. (2009) Compositional
and lithological diversity among brecciated lunar meteorites
of intermediate iron composition. Meteoritics & Planetary
Science 44, 1287–1322.
Chemical Classification
Overview | NWA
5207
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