The new research technique of selective adsorption and flotation for pyrite with flotation granularity and with artificially deposited gold grain from H[AuCl₄] solutions is proposed for reagents, using for gold flotation. The fact that flotation activity of new collector of oxypropyl ester of diethyldithiocarbamic acid (OPDTHC) is higher than this activity of diethyldithiocarbamate relating to pyrite which beneficiated by gold is established. Necessity of more long contact between OPDTHC and the mineral before flotation is shown. Investigations of pyrite after gold precipitation were conducted using analytic scanning electron microscope equipped by X-ray energy-dispersive micro analyzer. Metal gold island precipitates were conducted using different size down to nanosize are found out on the surface of pyrite grains. Sorption of OPDTHC on pyrite, which beneficiated by gold, was investigated with photometric method. Sorption was fixed on the pyrite areas, covered with gold, using microprobe analysis of changing X-ray spectra.