Tucked near the top of a drystone wall, the stone had been repurposed as ordinary building material, its carved face pressed inward and hidden. Only its colour and texture distinguished it from the surrounding grey limestone. Once turned, it revealed the upper half of an Early Christian cross-slab, roughly triangular and measuring approximately 40cm by 40cm, with a fine cross and a partial inscription pecked into its surface.

The slab belongs to what scholars classify as Clonmacnoise-type, specifically O'Floinn's Type B, a category dating from the later ninth century to the end of the tenth century. Type B cross-slabs carry a Latin cross with a central circular expansion and semicircular terminals, sometimes looped, a design associated with the great monastic centre at Clonmacnoise on the Shannon, not far to the south. The wall that concealed it belonged to the Smyth family of Portlick Castle, whose rectangular burial enclosure is visible on the revised 1914 Ordnance Survey map sitting within the centre of an older, D-shaped graveyard. That earlier graveyard appears to have been laid out inside the bailey of a motte castle, a Norman-era earthwork consisting of a raised mound with an adjoining enclosed yard, which may itself have been constructed over an early Christian ecclesiastical enclosure. The drystone wall of the Smyth enclosure also incorporated architectural fragments from a late medieval building, possibly the remains of a church that once stood within the earlier graveyard. Layer folded upon layer, each one quietly overwriting the last. The cross-slab is now held by the National Museum of Ireland, which is where it has been since its discovery.