The triforium is the gallery level set between the main arcade and the clerestory windows in a medieval church, a dim, corridor-like space not generally open to the public and seldom on anyone's itinerary. The slab sits built into the ceiling above the central pier on the south side of the choir, which means it was deliberately incorporated into the fabric of the building rather than lost or discarded. It is one of those details that rewards the kind of attention most architecture never receives.

The slab is granite, with an exposed face measuring roughly 46 centimetres long by 37 centimetres wide. Its carved decoration is restrained but deliberate: a shallow recessed cross set within a double incised circle, with small subtriangular recessed areas filling each of the four quadrants between the arms of the cross. This type of grave marker, with its combination of a ringed cross and geometric infill, is associated with early medieval Irish stonework, though the slab's precise origins and the identity of whoever it once commemorated are not recorded in the available documentation. Its presence in the ceiling fabric suggests it was reused as a building material at some point, a common enough fate for older stonework when later construction or repair work demanded convenient dressed stone. The detail is noted in Swords, K. ed. 2009.

Access to the triforium level is not a routine part of any visitor experience, and the passage itself is not publicly accessible in the ordinary course of a church visit. Anyone with a specific research interest in the slab would need to make arrangements directly with the relevant authorities. The slab is not visible from the nave or choir floor below, so there is nothing to see from ground level. What makes it worth knowing about is less a matter of what you can observe and more a matter of what it implies: that the building contains, worked into its very structure, fragments of an earlier devotional and funerary landscape that were simply absorbed rather than preserved, their original context quietly erased in favour of usefulness.