Abstract
I present the results of an analysis of [Fe IV] emission in several ionized nebulae, which is based on new identifications and previous measurements of [Fe IV] lines. The Fe abundances obtained by adding the abundances of the relevant Fe ions (mainly Fe^++ and Fe^3+) are found to be lower, by factors in the range 2.6-5.9, than the Fe abundances implied by [Fe III] emission and an ionization correction factor derived from ionization models. The possible reasons behind this discrepancy are discussed, as well as the implications it has for our understanding of both the evolution of dust in ionized nebulae and the chemical history of low metallicity galaxies.
