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Northwest Africa 2516
Algeria
Found 2004
Achondrite (eucrite)
Two stones weighing 224.6 g and 71.2 g respectively were purchased in Erfoud in September 2004. Fusion crust is fissured and altered. Classification and mineralogy (M. Bourot-Denise, MNHNP): the dominant texture is gabbroic to microgabbroic, with twinned pyroxene crystals (pigeonite-augite) of variable sizes, and large plagioclase laths. Orthopyroxene makes up large clasts, with abundant opaque (sulfide) inclusions. Areas of silica with irregular outlines are commonly associated with plagioclase, and contain blebs of oxides (ilmenite and chromite), troilite and metal. The most abundant mineral is pigeonite Fs51.6 Wo4.4, with exsolution of augite Fs26.7 Wo41.6; orthopyroxene Fs56.4 Wo2.9. Magnetic susceptibility 3.23 (J. Gattacceca, CEREGE, Aix en Provence) Weathering grade W2. |
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