[en] For an express control of useful components in ores and in final enrichment products a standard-background method is suggested, based on irradiation of the controlled medium by soft gamma-radiation fo radioactive isotopes with the following recording of the X-ray fluorescence flux, the intensity of which depends on the component content. Analytical parameter of the method suggested is the ratio of the X-ray fluorescence flux value to the scattering radiation value. The formulas and the method for X-ray fluorescence flux calculation are presented. The dependence of the above parameter on the Nb, Ta, Fe, W, Mo, Zr content is studied experimentally using the samples with known component concentration. The dependence is expressed by the line diagram. The method is tested under conditions of a concentrator shop. Its technique is simple and rapid, errors meet the requirements of the production