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[PolandMet]
History and physical
characteristics: A 1276g desert-weathered, brownish stone was purchased in Erfoud, Morocco in
October 2007.
Petrography (J. Wittke and T. Bunch, NAU): Contains a magnificent collection of closely packed,
pristine chondrules. All varieties of chondrules are represented with Type I (FeO-poor) dominant over
Type II (FeO-rich) by a ratio of 3:1. The abundance of chondrule textural types are PP > PO > POP
> GOP > RP > C > R > BO with several heavily mantled and unique types. SEM imagery and
x-ray mapping show no evidence of devitrification in chondrule mesostasis, mostly homogeneous mesostasis,
and alkali-poor mesostasis compositions. Weathering grade is W3 with minor iron staining in thin section.
Mineral compositions: Cr2O3 content in olivine is consistent wit a
classification of < subtype 3.1. Until high quality analyses are performed on chondrule mesostasis
for K and Na contents and distributions, a 3.0 subtype is not warranted at this time.
The only types LL3.05 classified up to date: QUE 97008, MET 00526, EET 90161 |
