The study of discrete-inelastic effects in rocks during the seismic-wave propagation is presented in this article. The laboratory and field experiments have been conducted to detect a discrete in elasticity. Data are obtained thanks to seismic recording "stress as a function of time", σ (t), with the microsecond-resolution. The inelastic manifestations are seen on the stress profile, σ (t) and are presented in the form of the stress plateau and the stress drop. Using the analysis of modern achievements in the solid-state physics and molecular dynamics can be drawn a conclusion to the effect that rocks possess by property of discrete in elasticity. Micro plasticity mechanism is the most appropriate for description of obtained results. The observed effects depend on the magnitude of the static and the dynamic stress. The discrete in elasticity can be important in wave dynamics, oil and gas geophysics, solid-state physics, and probably this property exerts influence on global deformation processes in the Earth in the ultra-low frequency range.