Unequilibrated ordinary chondrite, brecciated (LL3,br; S2; W3)
Found, 2015 or earlier; 1.816 kg

A moderately large single meteoritic stone was purchased in Tucson. Inspections revealed distinct chondrules (~0.4 mm, ave diam.), chondrule fragments, CAIs, and an unusual carbonaceous chondrite clast within an encompassing fine-grained matrix (60 vol%). Textures and average compositions of olivine (Fa28.1±1.8) and twinned low Ca-pyroxene (Fs15.9±8.8) are generally characteristic of unequilibrated LL3 ordinary chondrites. Compositional extremes within silicates [forsterite and clinoenstatite, sensu stricto, along with anorthite and augite grains] as well as LL5, LL6, and C chondrite clasts are, however, often outside the normal textural, mineralogical, and chemical range of 'ordinary' LL3 meteorites. Chondrule diameters range from 0.12 — 0.8 mm and include all major textural varieties (porphyritic, radial, barred, cryptocrystalline, and granular types) with porphyritic pyroxene-rich (PP) types particularly prominent. Original Fe-Ni metal content (kamacite and taenite) was originally ~2-3 vol%. The complex textures — cited in the references and described in detail by Rubin et al. (2017) — are such that NWA 10214, unlike most well-described unequilibrated LL chondrites, has not been assigned a specific subtype. Rubin et al. (2017) thought that the presence of L5 and L6 clasts makes an L3-6 classification more appropriate. Perhaps an 'LL3, anomalous' label would be more accurate. Undulose extinction in most coarse olivine grains and the lack of planar fractures support an S2 shock stage. With ~70% of the Fe-Ni altered to limonite the meteorite has been assigned to the W3 weathering stage. In addition to the pervasive limonite stains, weatherate pentlandite is also present.

NWA 10214 is one of 502 recognized LL3 ordinary chondrites with approved names posted at the Meteoritical Bulletin Database as of early March 2017. As most recovered LL3 chondrites are quite small (median mass ~100 g), the 1.8 kg NWA 10214 is a welcome addition to this mineralogically diverse subset of LL-group meteorites.

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