Various calibration steps are necessary before the QEMSCAN analysis. The X-ray spectrometers, the backscattered electron (BSE) image, the probe current, the spectral engine, the image magnification, and the BSE shift are calibrated. At a QEMSCAN measurement the sample surface is mapped in a stepwise pattern. QEMSCAN collects both X-ray signals and backscattered electron image signals from each analysis point of the scan raster. In the following, the elements of each X-ray spectra are identified and quantified. The elemental intensities are compared against a library of minerals (Species Identification Protocol – SIP), following a specific set of rules. For each match the relevant analysis point is assigned to a mineral or phase.