Iron-doped zirconium silicate. Part 1.—The location of iron

Abstract

Iron-doped zirconium silicate (zircon) has been shown by X-ray powder diffraction (XRD), energy dispersive X-ray analysis (EDX) and ⁵⁷Fe Mössbauer spectroscopy to consist of inclusions of α-Fe₂O₃ together with discrete paramagnetic Fe³⁺ species within the zircon structure. Electron paramagnetic resonance (EPR) spectra show that the Fe³⁺ species in the samples containing less than 0.2 mass% Fe occupies low-symmetry rhombic sites, but that in materials with higher concentrations of iron the Fe³⁺ also occupies other locations, including sites with axial symmetry. The colour of the iron-doped zircon is due to both the low symmetry Fe³⁺ species and the inclusions of α-Fe₂O₃.