My thoughts concur with TheCannonballGuy on this item. The size, shape, and uniform edges on the square hole, are consistent with what is seen on turn knobs for wick adjustment on lamps of the mid through late 19th Century, and even into the early 20th Century. Often these knobs have reeded edges to assist in finger grip, and when found individually, resemble small coins or tokens.
A square nail punched through a coin or token, will leave a deformed surface, with the edges of the hole pulled down on the side of first puncture, and then pushed out on the opposite side. My very first Flying Eagle penny found, had a hole in the center, apparently caused by a square nail being hammered through. The coin and the hole both were rather on the rough side.
CC Hunter