Methods are described for the determination of major and minor chemical constituents in fine-grained sedimentary rocks. They include wet-chemical methods, radiometric and flame-photometric methods, absorption and emission spectroscopic methods, and fluorescent X-ray procedures. The major elements are determined by a rapid semi-micromethod on 2 samples, one of which is decomposed by fusion with sodium carbonate; the other sample is decomposed by digestion with sulfuric and hydrofluoric acids. Trace elements are determined by spectrochemical procedures using internal standards. C, S, and the C present in carbonate minerals are determined by conventional methods. A fluorescent X-ray spectroscopic method for Fe and Mo is described.