The X-ray radiometric method is realized in a line-of-sight geometry, when the detector is oriented so that it “sees” a part of the surface of the investigated medium irradiated by the source. In this geometry the detector registers mainly single scattered gamma-quanta and X-ray fluorescence of the element to be determined. A secondary role is played by multiple scattering, the influence of which is significantly reduced by collimation of primary and secondary radiation. When using soft gamma radiation sources (energy e=70-80 kev), measurements can be made in a wide solid angle. In ordinary cases, the spectra of secondary radiation have a general character.