The injured was installing a rib bolt in the #2 heading on 28 Right Section when a rock measuring 19"" L X 9"" W X 6 1/2"" Thick fell from the area of the ATRS striking the injured's left hand resulting in an avulsion the tip of the middle finger. The employee was taken to Clinch Valley Medical Center where the top tip of left middle finger was surgically amputated.