Northwest Africa 14529 (NWA 14529)

(Northwest Africa)

Purchased: 2020 Mar

Classification: Iron meteorite (ungrouped)

Petrography: (J. Gattacceca, CEREGE) The etched section shows a plessitic octahedrite structure with remnants of fine scale Widmanstätten patterns (50 µm bandwidth). Veins of swathing kamacite, 100 µm thick, crosscut the sample. Rounded mm sized silicate inclusion are found, consisting of pyroxene, plagioclase and olivine, in decreasing amount. Plagioclase shows lobate contacts with pyroxene and olivine. Chromite is present as 50 µm grains.

Geochemistry: (H. Pourkhorsandi and V. Debaille, ULB): Composition of the metal (ICP-MS) is Co=0.42±0.01, Ni=10.41±0.07 (both in wt% ± 1 sigma), Cr=5.5±0.1, Cu=247±2, Ga=16.9±1.1, Ge=3.9±0.6, As=10.0±0.4, Mo=3.83±0.07, Pd=3.96±0.08, W=0.57±0.06, Ir=2.4±0.3, Au=0.77±0.05 (all in ppm ± 1 sigma). Oxide compositions (EPMA, J. Gattacceca): Olivine Fa_20.8, FeO/MnO = 43.0 (n=2); Low-Ca pyroxene Fs_17.9Wo_2.4, FeO/MnO = 26.8 (n=2); Plagioclase An_11.6Ab_83.0Or_5.4 (n=2); Chromite Cr# 0.82.

Classification: Iron meteorite (ungrouped). Although the metal metal composition is reminiscent of IIE irons, the Ge content is lower than in IIE irons. The silicate composition is also different from that in IIE irons, and similar to the silicate composition in H chondrites (see figure 3 in Schrader et al., 2017).

Specimens: Type specimen at CEREGE. Main mass with Kuntz.