The results of pilot-researching works of estimation of quality of bank slope work of rock binary ledge with 24 m highness with preliminary chink formation by the way of explosion of contour blasthole charges with their initialization by electronic detonators of I-kon^TM system and Eksel non-electrical system have been presented. These results were realized at Kovdorskiy mining and concentration plant. Deficiency of  important advantages of electronic detonators in quarry conditions has been established.