Highly oxidized iron oxides such as SrFe4+O3, CaFe4+O3, and CaCu3Fe4O12 display unusual electronic and magnetic behaviors due to the highly covalent nature of the Fe-O interaction. Topochemical oxidation using high oxygen pressures leads to the formation of a new phase with composition Ca2FeCoO6. Magnetisation data show this material is ferrimagnetic with a transition temperature of approximately 220 K. We have used high temperatures and pressures to make oxygen stoichiometric Ca0.5Bi0.5FeO3 which shows novel charge ordering transitions at 200 and 250 K. We therefore request 2 days on GEM in order to characterize the two above materials. A standard 10-300 K CCR will be sufficient to record diffraction patterns as a function of temperature from a 1 g sample of Ca2FeCoO5 (~5 hours) and a 0.1 g sample of the high pressure Ca0.5Bi0.5FeO3 product (~43 hours).