Synchrotron X-ray fluorescence analysis (SXRFA) is compared with other microanalytical techniques including electron microprobe analysis (EMPA), particle-induced X-ray emission (PIXE), particle-induced gamma-ray emission (PIGE), nuclear reaction analysis (NRA) and secondary-ion mass spectrometry (SIMS). X-ray fluorescence spectra were taken of 21 feldspars and synthetic glasses to establish an experimental protocol and suitable standards for routine microprobe analysis of minor and trace elements. The white X-ray beam from a bending magnet of the 2.5-GeV National Synchrotron Light Source was apertured to 0.03 × 0.06 mm. The fluorescent X-rays were detected with an energy-dispersive system oriented at 90° to the incident beam. Spectra were obtained from each polished thick-section oriented at 45° and two sets of spectra were obtained for the crystalline feldspars at different orientations to evaluate the diffraction interference. Each spectrum was stripped using an interactive Gaussian-fitting program STRIP and elemental sensitivities were determined theoretically by the NRLXRF X-ray fluorescence analytical program without the use of external standards. Detection levels (part per million weight: 2σ) are: Ba and Ti (40), Mn, Fe, Cu, Zn, Ga, Ge, Rb, and Sr (2) and Pb (20). The higher values for Ba and Ti result in part from spectral overlap, and that for Pb from lower sensitivity for L spectra. The resulting standard-less elemental concentrations were compared with electron microprobe analyses of the same thick-section of each feldspar, and with atomic absorption spectrophotometry (AAS) of a fragment or slice. Concentrations determined by the three techniques agree to within ∼ ±20% with two exceptions. Rb contents determined by AAS agree with standard-less SXRFA and standard-controlled EMPA within only a factor of 2. Ba contents appear to be underestimated by standard-less SXRFA by ∼30% probably due to systematic errors in fundamental parameters used to obtain theoretical yields for Ba- L α fluorescence: hence, an external standard or an empirical correction is desirable. These results demonstrate that many trace elements in feldspars can be usefully determined by a simple standard-less technique referred to the major elements. Although the goal of this work has been the development of analytical protocols, valuable crystal-chemical data have been obtained including definitive evidence for substitution by Cu and Zn.