Arispe meteorite, Arizpe, Mun. de Arizpe, Sonora, Mexico

Iron meteorite (IC, Og)
Find, 1896; 683 kg

A 123 kg iron mass (Ni>6.5%) was found ~25 km NW of Arizpe (also, 'Arispe') with well over ten additional fragments recovered in subsequent decades. A 122 kg mass obtained by Nininger had been uses as an anvil for several decades but overall seemed little the worse for all the hammering it had received. Kamacite with Neumann bands is prominent. Small regions are significantly corroded, but the fusion crust has managed to protect much of the interior portions of most well-studied fragments [50x35x10 cm and smaller]. Troilite is irregularly distributed as small nodules. Very unusual nests of cohenite have apparently contributed to local, hardened martensite-rich regions. Schreibersite is present as laths, hieroglyphs, rhabdites, and grain boundary precipitates. Plessite and taenite are present, but not abundant (~2 vol%). Very minor amounts of carlsbergite particles and exsolved daubréelite are present. Isotopic studies (e.g., Hf-182 in Arispe) suggest that the epoch of core formation for many iron meteorites were surprisingly brief (<10 Ma). On the other hand, a terrestrial exposure age of ~250,000 years for Arispe suggests that the Arispe fragments have lain in the dessert for a surprisingly long time.

Arispe is the 5th most massive of the small twelve-member IC iron meteorites listed at the Meteoritical Bulletin Database (as of August 2015). In 2015 the largest Arispe holdings, including the intact anvil, were being held at Arizona State University (133 kg). Masses of 35-75 kg, however, were held in several other museums as of 2000 [Cf. Catalogue of Meteorites (5/e)]. Synonyms: One fragment has also been known as 'Moctezuma (of F. Berwerth)'.

Mineral List

9 entries listed. 6 valid minerals.

References

External Links