NWA 10503 – 7.85g

$1,100.00

1 in stock

Description

Achondrite, ungrouped

7.85g endcut
Sold with label/certificate of authenticity


a unique recrystallized specimen with affinities to carbonaceous chondrites, but with oxygen and chromium isotopic compositions unlike those for any known meteorite classes“. Irving, Kuehner, Ziegler, 2016 (79th Annual Meeting of the Meteoritical Society)

 

Northwest Africa 10503 (NWA 10503)
(Northwest Africa)
Purchased: 2015 May

Classification: Ungrouped achondrite

History: Purchased by Fabien Kuntz in May 2015 from a dealer in Zagora, Morocco.

Petrography: (A. Irving and S. Kuehner, UWS) Triple-grain-junction texture, grain size 0.1-0.7 mm. Very fresh assemblage of predominantly olivine with subordinate clinopyroxene (~20 vol.%), intermediate plagioclase (~10 vol.%), and accessory pyrrhotite, chromite, taenite and pentlandite.

Geochemistry: Olivine (Fa31.8-32.0, FeO/MnO = 79-96, N = 3), clinopyroxene (Fs11.4-11.6Wo42.5-42.6, FeO/MnO = 43-44, N = 2), plagioclase (An32.3-33.9Or3.2-3.0). Oxygen isotopes (K. Ziegler, UNM): analyses of nine acid-washed subsamples by laser fluorination gave, respectively, δ17O -3.757, -3.884, -3.950, -3.557, -3.569, -3.779, -3.674, -3.818, -3.968; δ18O -0.848, -1.162, -1.212, -0.555, -0.624, -0.873, -0.792, -0.893, -1.206; Δ17O -3.309, -3.270, -3.310, -3.264, -3.240, -3.318, -3.256, -3.346, -3.331 per mil.

Classification: Achondrite (ungrouped). Despite similarities in texture this meteorite has an oxygen isotopic composition far removed from those of any brachinites, winonaites, and acapulcoites.

Specimens: 26.3 g including one polished thin section at PSF; main mass with Kuntz.