The article presents the results of a laboratory investigation of spectral induced polarization (IP) carried out on synthetic models of disseminated ores. The models are represented by mixtures of sand (the grain size is 200-300 μm) and electron-conductive ore minerals with different grain sizes. The research examines IP with different current wavelength forms in a time range from 0,3 ms to 64 s. We used a Debye decomposition approach to obtain IP spectra. We studied relationships between the chargeability, averaged differential polarizability and IP spectrum parameters, and the radii and concentrations of the ore minerals. We obtained the following results: The total chargeability is linearly related to the concentration; the average relaxation time, τ , depends on the particles diameter, d, as τ ∝d² . We also show an efficiency of using the Debye decomposition approach for interpreting IP data in mineral exploration.