WHILE WORKING ON CRUSHER, PRIMARY CONVEYOR BELT STOPPED. WE FIGURED IT WAS EITHER THE GEAR BOX WENT OUT OR A ROCK. CRUSHER WAS SHUT DOWN & BELT WAS NOT RUNNING. I WALKED OVER TO RETURN BELT & STUMBLED ON SOME LOOSE ROCKS, LOST MY BALANCE. I HAD PRY BAR IN MY HAND TRYING TO PRY A ROCK LOOSE IF NEEDED. THE PRY BAR FELL AGAINST RETURN BELT, BOUNCED & CAUGHT ME ON LEFT SIDE OF LEFT EYE