IIIE irons
IIIE irons are a small group of coarse octahedrites closely related to IIIAB irons but containing haxonite.
IIIE irons are a small chemical group of iron meteorites, with around fifteen members. They are coarse octahedrites that resemble the large IIIAB group in many ways, but differ in trace elements such as gallium, germanium and tungsten, and especially in their minerals: many IIIE irons contain the iron-nickel carbide haxonite, which is rare in IIIAB irons.
Their kamacite bands also tend to be broader and slightly different in shape. Examples include Kokstad from South Africa.
For some time, IIIE irons were considered possibly part of IIIAB, but detailed chemistry and isotopic work showed they formed in a separate core. Groups like IIIE demonstrate how careful analysis can separate meteorites that look similar to the eye. Their carbide content suggests the metal crystallised from a liquid relatively rich in carbon, a clue to the composition of its parent asteroid.
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