Powder X-Ray Diffraction (pXRD or simply XRD) is an analytical tool that utilizes a collimated beam of X-rays to scan a sample surface at changing angles to produce a spectrum according to Bragg’s Law. A peak is produced when the sample/mineral contains lattice planes with d-spacing to diffract the X-rays at specific angles. It is used primarily for the phase identification of bulk crystalline materials, but can also be used for unit cell determination, the determination of relative amounts of phases within a mixture, thin film characterization and to measure particle size and strain/stress.

Powder XRD is used extensively in geology, chemistry, material science and engineering but it can be used to identify any solid, crystalline material.