USING LONG BAR AGAINST LUMP OF SAND, WHILE ANOTHER EE WAS TRYING TO BREAK UP LUMP WITH SLEDGE HAMMER. BOTH EMP. STANDING ON CONVEYOR BELT. LUMP SPLIT IN TWO. ONE HALF FELL TO BELT, BUT OTHER H ALF FELL ON IRON BAR HELD BY INJURED EE. FORCE CAUSED BAR TO LIFT CUTTING EE S FACE, JAW, AND THROWING HIM OFF BELT. EE LANDED ON FLOOR APPROX. ONE FOOT FROM BELT.