How do X-ray diffraction patterns identify different minerals?

In geology, X-ray diffraction is a powerful diagnostic tool used to identify minerals by analyzing their internal atomic structure.12

Because minerals are generally crystalline, they possess a uniform arrangement of atoms that act as a diffraction grating for X-rays. When an X-ray beam passes through a mineral specimen, the rays are diffracted at specific, regular angles determined by the spacing between the mineral's atomic planes. This process is governed by the Bragg law, expressed as $n\lambda =2d\sin \theta$, where the interference of reflected waves creates a distinct pattern.132

These patterns are recorded as a series of lines with specific positions and intensities, which serve as a unique "fingerprint" for each mineral species. By comparing these diffraction patterns against known standards, crystallographers can definitively determine the internal structure and identity of a mineral, even when the specimen is too minute for traditional optical identification.24