X-ray diffraction patterns of mineral phases: amethyst (quartz), graphite, and calcite

This dataset contains raw X-ray diffraction (XRD) patterns of mineral phases: amethyst (quartz), graphite, and calcite. The data were acquired using powder X-ray diffraction equipment D8 Bruker Advance, with Cu Kα radiation over a 2θ= 10-90° range. Amethyst and graphite were collected with step size of 0.03° and time step of 0.5 s; calcite was measured with step size of 0.04° and time step of 0.5 s. This dataset is intended to serve as a reference resource for mineral identification, teaching applications, and validation of diffraction-based methodologies. The data are provided without prior processing.