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NWA 2627 Found 2004 A 68g mostly crusted, partial stone was purchased in Erfoud in October 2004. Description and classification (T. Bunch and J. Wittke, NAU): recrystallized into polygonal and subhedral grains with the exception of large orthopyroxene grains (up to 3 mm) that poikilitically enclose olivine; heavily fractured, variable grain size, and heterogeneous distribution of phases. Modal analyses (vol. %): orthopyroxene, 44; olivine, 41; FeS, 6; metal (and Fe-oxides), 5; plagioclase, 3 and minor merrilite, Ca-pyroxene and chromite. All silicates have very homogeneous compositions; olivine, Fa13.1, FeO/MnO = 26; orthopyroxene, Fs12.2 Wo2.7, FeO/MnO = 13.9; plagioclase, An21.9; metal, Ni = 6.7 wt % Ni. Oxygen isotope analyses are consistent with winonaites, mineralogy and mineral compositions are more consistent with lodranite assemblages. Weathering grade is W2/3 with ferric Fe staining; shock level is S2. Specimens; type example, 13.7 g, NAU: main mass, Strope/Farmer. This is a very rare meteorite, resembling the Lodranites more than the Winonaite. Only the Oxygen isotopes plot in the Winonaite field. This is a new one, and certainly one for the type collectors. |
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