A stable hydrophobic concentrate of silver nanoparticles in decane with a concentration of 1 mol/L and a particle diameter of about 10 nm has been obtained by nonaqueous electrophoresis in a condenser-type electrophoretic cell at an electric field of 600 V/cm. The concentrate and its redispersants in various solvents have been investigated by electrophoresis, spectrophotometry, photon-correlation spectroscopy, transmission electron microscopy, and diffraction using X-ray synchrotron radiation. The electrokinetic potential of the silver nanoparticles was 80 mV, and this makes it possible to reduce the response time of the electrophoretic monitors to 0.03 s. The interplanar spacing (0.234 nm) and unit-cell parameter (0.4065 nm) of the nanoparticles virtually coincide with the data obtained for bulk samples of silver.