NORTHWEST AFRICA 305


E3
(probably EL3)
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purchased December 2000
no coordinates recorded

A 210 g meteorite was purchased by Canadian meteorite dealer D. Bessey in Erfoud, Morocco. Upon cutting, it was considered that it was a particularly nice LL3 and was used to make thin sections. Thereafter, a 34.7 g sample and a thin section were sent to the Russian Academy of Sciences in Moscow for analysis and classification. The preliminary analysis conducted by S. Afanasiev (Vernad) led to the determination that this was an E3 chondrite (Fs1.11, An10.8) with a shock stage of S2 and a weathering grade of W3.

From the preliminary data, including the fact that the chondrule diameter is relatively large compared to EH chondrules, it might be inferred that NWA 305 belongs to the EL chondrite group. Only a few EL3 chondrites are currently known, including several from the Antarctic (e.g., ALH 85199, MAC 88180, and PCA 91020), one from Australia (Watson 007), EL3 xenoliths identified in the carbonaceous chondrite Kaidun (designated Kaidun IV) and in the ureilite Almahata Sitta (designated MS-MU-002), and a few from Northwest Africa (e.g., NWA 3132, NWA 6508, NWA 7406). Therefore, NWA 305 could eventually prove to be an important addition to this highly unequilibrated enstatite meteorite suite. Further information on the classification determinants and the petrogenesis of the E chondrites can be found on the Saint-Sauveur page.

The specimen of NWA 305 shown above is a 5.17 g partial end section. Shown below is a comparison between the E3 chondrite NWA 305 in the top composite photo, and two EL3 chondrites in the bottom composite photo, comprising NWA 6508 (bottom) and NWA 7406 (top). It is obvious that there is a very close similarity in the appearance of chondrules and matrix among all of these meteorites, and it is probable that NWA 305 is an EL3 chondrite.

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Photos courtesy of Dean Bessey

standby for northwest africa 305 photo
Photos courtesy of Jason Utas; see more here >> fallsandfinds.com