XRD is complementary and competitive to other analytical methods. A strength of XRD is it´s sensitivity to fine particle fraction. The XRD sample preparation is quick and simple. Only XRD can distinguish polymorphs (e.g. TiO2 in the form of rutile or anatase) and polytypes (e.g. Muscovite 1M or 2M1).
XRF measures the concentration of major elements mostly from fused glass beads. Volatile components such as CO2, H2O, and OH, are lost in preparation (Loss on ignition, LOI). They need to be analyzed separately for a full quantification. XRD directly looks at the hydroxide and clays mineralogy in iron ore.
Raw iron producers are major greenhouse-gas pollutants. The CO2 footprint of a pig-iron plant is mainly governed by the overall oxidation state (Fe2+/Fe3+) of iron in the ore. The oxidation state determines the amount of reducing agent (coal) in raw iron production and is obtained from the mineralogy of the ore. XRD is not only fast but virtually operator independent, especially when compared to wet chemical methods such as titration.