INJURED WAS TALKING WITH SECTION FOREMAN WHEN A PIECE OF DRAW ROCK APPROX 24"" X 18"" X 3"" FELL AND STRUCK HIM IN THE RIGHT SHOULDER. HE FINISHED HIS SHIFT AND CONTINUED TO WORK HIS REGULARLY SC HEDULED SHIFTS UNTIL 5-30-01. HE SOUGHT MEDICAL ATTENTION AND WAS ADVISED TO REMAIN AWAY FROM WORK UNTIL FURTHER NOTICE. THE SAFETY DEPT. WAS NOT NOTIFIED UNTIL 6-4-01.