It measures just 33 centimetres high and 29 centimetres wide, not much larger than a hardback book, yet its surface carries the kind of ornamental carving that speaks to a medieval craft tradition far older than the building currently housing it. The decoration includes chevron, stepped, and dot patterns, the dense geometric vocabulary characteristic of Romanesque stonework, a style that flourished in Ireland during the twelfth century and is recognised by its rounded arches and elaborate surface ornament.

The stone is thought to have originated as an arch stone, possibly from a Romanesque doorway that was at some point inserted into the south wall of the church. Romanesque doorways were among the most elaborately decorated features of early medieval Irish ecclesiastical architecture, and even a single voussoir, one of the wedge-shaped stones that together form an arch, can carry significant carving. How this particular fragment came to rest beside the font, separated from its original structural context, is not recorded, but the displacement itself is not unusual. Architectural salvage and reuse across centuries of church repair and rebuilding was common practice, and fragments like this one often survive precisely because later builders recognised them as worth preserving, even when the original doorway or arch no longer existed.