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Some L-chondrite meteorites found in the arid desert region of Roosevelt County in New Mexico, USA, and C-14 dated to determine the terrestrial age have been examined by Fe-57 Mossbauer spectroscopy. The preliminary results reported here suggest that the initial weathering processes involve oxidation of iron in the iron-nickel alloy. After prolonged exposure to terrestrial weathering for approximately 36 000 years, the iron(II)sulphide and -silicate phases are also oxidised. The corrosion products are complex and include paramagnetic Fe3+ species and macroscopic iron(III) oxide and/or oxyhydroxide phases. A meteorite which fell approximately 16 500 years ago at the end of the last glaciation showed extensive corrosion despite its relatively short terrestrial age. The result is associated with climatic changes which occurred at that time.