The object of the research is the electric-pulse method of materials destruction. The aim of the work is to establish the mechanism of destruction of heterogeneous materials, to choose the energy parameters of pulses, which ensure minimum energy consumption for the process of destruction of kimberlites and maximum safety of isolated diamonds, to develop and create a pilot plant for the process. The conditions of discharge formation in the kimberlite-water system were found. DIK-1M unit was modernized and assembled. Pulse amplitude, interelectrode gap were taken as variable parameters, condensate battery capacity as constant ones. Optimal pulse parameters were selected. Intact diamond crystals were isolated. The results were analyzed.