IIE irons
A non-magmatic iron group containing silicate inclusions related to H chondrites.
Among iron meteorites, IIE stands out as a small, non-magmatic group notable for silicate inclusions. Its metal does not show the tight trace-element trends of a crystallising core, and the silicates span a wide range: some are nearly unmelted chondritic material, others are partial melts or highly differentiated, glassy and feldspar-rich rocks. Oxygen isotopes of the silicates resemble those of H chondrites, so a genetic link to the H-chondrite parent body, or a similar body, is widely discussed.
IIE irons are thought to record impacts that melted metal and mixed it with rock on a chondritic parent body, producing pools of metal that trapped fragments as they cooled. Some IIE silicates have been dated to ages younger than the earliest Solar System, pointing to later impact events. Examples include Weekeroo Station and Watson from South Australia, Miles from Queensland, Netschaëvo from Russia and Colomera from Spain.
On a cut face, IIE irons show grey or greenish silicate globules and angular fragments, centimetres across, set in metal that may be fine to medium octahedrite. Their striking appearance makes them sought after, but classification depends on metal chemistry and silicate oxygen isotopes.
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