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Results from high-pressure experiments combined with geophysical data have indicated that majorite is likely a dominant phase in the transition zone. Due to its variable oxidation state, iron is expected to play a major role in determining the physical and chemical properties of majorite. As a first step to characterize the effect of iron on majorite, we have examined the system (Mg,Fe)SiO₃. Samples were synthesised using a multianvil press at varying oxygen fugacity conditions. All samples were examined using the electron microprobe, Mössbauer spectroscopy, powder X-ray diffraction and optical spectroscopy. Results show that Fe³⁺/Fe in (Mg,Fe)SiO₃ majorite increases with both increasing oxygen fugacity and total iron content. Rapid electron transfer occurs between Fe²⁺ - Fe³⁺, likely across the shared edge between the octahedral and dodecahedral sites. Fe³⁺ appears to occupy the octahedral site primarily, and the amount of Fe²⁺ in the octahedral site decreases with increasing Fe³⁺ content, coupled with an increase in unit cell volume. We are using this data to construct plausible defect models that balance the charge deficit caused by the substitution of Fe³⁺ for Si⁴⁺.