One small sandstone slab, carved with an early medieval cross, was among the pieces carried off, and by the time the Dean of Clonmacnoise intervened to stop its removal, the stone was already gone from the island. It had been absent for roughly twenty-five to thirty years before he acquired it in 1932, placing its departure somewhere around the turn of the century. The following year it passed to the National Museum of Ireland, where it has remained ever since.

The stone itself is modest in size, barely twenty centimetres tall and twenty-four wide, but the carving on its face is precisely executed and dates to the seventh century. The technique is known as false relief, meaning the background around the cross design has been pecked away so that the cross appears to stand proud of the surface, even though the carving is essentially flat. The cross has expanded terminals, with a square form at each arm-end and another at the central intersection, and the back of the slab has been worked in a corresponding cruciform pattern. This kind of careful, symmetrical decoration is characteristic of early Irish ecclesiastical stonework, and Inchcleraun, an island with a long monastic history on the Shannon, would have been a natural setting for such an object. The slab is incomplete, so whatever broader composition it once belonged to can only be guessed at.