Phase identification by XRD is the most common and most accurate method of determining the crystallographic phases of solids or slurries. The “phase” of a material not only reports the elements present, but also the chemical formula and structure. For example, phase identification by XRD can determine the quantitative ratios of anatase and rutile (two different phases of TiO2), or magnetite and hematite (two different phases of FeOx). XRD can also determine and quantify the various polymorphs in pharmaceuticals.

This technique is often coupled with XRF (x-ray fluorescence) for more accurate atomic percentages.

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