It is plain, uneven, and just over a metre long, set face-up on the ground in the manner of a recumbent graveslab, the kind of marker laid horizontally over a burial rather than set upright. It bears no carving, no inscription, no ornament of any kind. What makes it quietly notable is precisely this absence, and the fact that it was recorded but passed over.

When the scholar R. A. S. Macalister surveyed the graveyard in 1916 and 1917 and produced his detailed plan of the site, he drew this slab in among the others but assigned it no number, leaving it catalogued in outline only. The stone sits in the eastern half of the graveyard, roughly 10.65 metres from the northern wall and 11.6 metres from the eastern wall, coordinates precise enough to locate it but doing little to explain why it was omitted from the numbered sequence. Inis Cealtra, sometimes called Holy Island, was an important early medieval monastic site, and its graveyard contains a variety of carved and inscribed stones accumulated over centuries of use. Against that company, a plain and unnamed slab is easy to overlook, which may be exactly what happened.