Northwest
Africa 2517
Boudnib
area, Morocco
Found 2004
Achondrite (ureilite)
One
completely crusted stone weighing 17.6 g was purchased
in Erfoud in 2004 September. Classification and
mineralogy (M. Bourot-Denise, MNHNP): olivine crystals
are mm-sized, with edges blackened by ribbons of
sulfide associated with metal. Alteration is evident
at grain boundaries. Metal and sulfide are intergrown.
Pyroxene is in large, fissured crystals with cleavage
planes blackened by fine sulfide blebs. Silicate
crystals are abutting to each other practically
without any interstitial material. Olivines are
zoned, with a composition varying from Fa~1.4 at
the edge up to Fa~22 at the center; mean at the
center Fa22.6 ± 0.2, 0.5 wt% Cr2O3, 0.3
wt% CaO; pyroxene (pigeonite) Fs19.0 ± 0.6
Wo8.9 ± 1.6, 1.2 wt% Cr2O3. Magnetic susceptibility
4.35 (J. Gattacceca, CEREGE, Aix en Provence).
Estimated shock stage S4, weathering grade W2.
Specimens: type specimen 3.3 g and one polished
mount, MNHNP; main mass with Philippe Thomas.
Meteoritical
Bulletin Database
NWA
2517, URE
© Ph.
Thomas (click to enlarge)
NWA
2517, URE
© Ph.
Thomas (click to enlarge)
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