A coal blasting technique that consists of firing an explosive charge in a borehole filled with water under pressure. The water is introduced through an infusion tube that also seals the hole. When the charge is fired, it produces in the water a high-pressure impulse that is transmitted into the numerous water-filled cleavage planes and slips and thus breaks the coal. The energy from the explosive is used more efficiently than when blasting in the conventional manner, and better coal preparation is obtained.