Figures 1-6 below show the XPS high resolution spectra of the elements on the surface of a freshly ground Feldspar sample. High resolution analyses are used to determine the various chemical species in the sample. Three component peaks were found in each spectrum corresponding to three different phases as listed below. There are many varieties of feldspar, but those commonly identified are Soda Feldspar (Na₂O • Al₂O₃ • 6 SiO₂), Potash Feldspar (K₂O • Al₂O₃ • 6 SiO₂), and the Calcium Fledspar (CaO • Al₂O₃ • 2 SiO₂). The Feldspar in the present case is a rather complex compound and has three different phases with Phase 1 as the major phase followed by the minor Phases 2 and 3. We have taken advantage of the differential charging of each of these species to identify each as a separate species. The same material without differential charging would appear to have the weighted average of these three compositions.

Phase 1: Na₂O • 0.76 K₂O • 1.59 Al₂O₃ • 12.64 SiO₂ • 0.84 H₂O
Phase 2: Na₂O • 0.33 K₂O • 1.26 Al₂O₃ • 7.86 SiO₂ • 8.48 H₂O
Phase 3: Na₂O • 0.19 K₂O • 1.62 Al₂O₃ • 7.25 SiO₂ • 9.79 H₂O