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Achondrite
Meteorites For Sale
Northwest Africa 2853
Northwest
Africa
Found 2005
Howardite
A 860g and a 140g fully crusted and
lightly weathered stone were purchased in Erfoud, Morocco.
Description and classification (T. Bunch and J. Wittke, NAU): dark gray,
highly shocked howardite
with a heterogeneous distribution of diogenite fragments that tend to be large
(2 to 9 mm in dia.).
Diogenite modes for 3 thin sections give 0, 9, and 15 vol. %. Eucrites
have a fine- to coarse-grained
size range and consist of subophitic and cumulate textured basalts. Host
pigeonite,
Fs45.3-51.7Wo5.8-9.0, FeO/MnO = 29-33; exsolution lamellae, Fs33.6-
39.4Wo19.0-25.4.
Diogenite orthopyroxenes, Fs22.6-25.6 Wo1.8-2.3, FeO/MnO = 24-27; plagioclase,
An89–94.3.
Most pyroxenes recrystallized into small, polygonal aggregates; plagioclase
melted,
although original grain boundaries are preserved (shocked beyond maskelynite
stability range),
and crystallized into fine-grained fibrous to radiating textures.
Specimens: type sample, 22 g, NAU; main mass, Regelman.
NW 2853 highly shocked Howardite
860g $15,999
NWA2853 Howardite 18g complete slice comes with Main Mass
NWA 1877 24g Fragment $2,400 Sold