These shots were taken in cross polarized light at a
magnification of 160X. Once again, this impressive thin
section was a loan from Jeff Hodges. If you know him,
give him a thanks for supporting science or the arts or
what ever it is I do.
Northwest Africa 999
Morocco
Find: 2000
Achondrite (eucrite)
History: A 330 g brecciated stone was purchased at the
Tucson show by D. Gregory from an anonymous Moroccan
dealer.
Petrology: (P. Warren, UCLA) An extremely fine-grained
(0.01–0.1 mm) stone with thoroughly exsolved pyroxenes,
some pyroxenes (<1 vol%) up to 0.6 mm in maximum
dimension. Microphenocrysts are compositionally
identical to the groundmass pyroxenes.
Geochemistry: Low-Ca pyroxene (En32.0Wo2.3); high-Ca
pyroxene (En27.8Wo44.1). Bulk chemistry: (INAA, UCLA two
chips) Al2O3 = 12.5 wt%, Na = 2.83 and 2.84 (both wt%);
Sc = 32 and 33; Sm = 2.1 and 2.2 (both µg/g); Fe/Mn =
36, 37.
Classification: Achondrite (eucrite); low to moderate
shock.
Specimens: A 20 g type specimen is on deposit at UCLA.
Gregory holds the main mass.










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