The aim of the RRUFF Project is that of creating "a complete set of high-quality spectral data from well characterized minerals". Moreover, RRUFF "is developing the technology to share this information with the world". Further information about the project is given in . In RRUFF we can find several spectra of natrolite. To decompose them, we will use the q-Gaussian functions (see Appendix). The identification of this mineral has been confirmed by X-ray diffraction and chemical analysis. Unoriented sample. Instrument settings: Thermo Almega XR 532nm @ 100% of 150mW. Data as given by the link, used in the range from 3000 to 4000 cm -1 . A spline baseline adjustment is applied.