Mössbauer Analysis of Meteoritic Iron Minerals

Abstract

The important role of iron in both the classification of meteorites and the investigation of their preterrestrial history was first shown by Prior [1, 2]. He introduced a chemical classification based on the Fe/Ni ratio of the metal phase and the MgO/FeO ratio of the silicate phase (see Table I) and found that these two ratios decreased together. Prior stated: “... in meteoric stones generally, the poorer they are in nickel—iron, the richer that iron is in nickel, and the richer in iron are the magnesium silicates.” The explanation advanced for this relationship was that meteorites have separated from a single magma which has passed through successive stages of oxidation so that as the metallic iron became progressively more oxidized the residual metal grew richer in nickel.

This work was performed under the auspices of the U.S. Atomic Energy Commission.