The injured was installing the last bolt in 2 Right Crosscut on 12 east section. While drilling they reached for a pusher steel and dropped it, as they reached down with left hand to pick it up. A piece of rock fell from the roof measuring 16""X 9""X 0-3"" thick fell 7 1/2' to the ground striking them on left hand. Resulting in an laceration which required 10 sutures to close.