Measuring just over a metre in height and less than half a metre wide, it is easy to overlook, yet its surface carries a raised ringed cross at its centre and a moulding running around its edge, details that mark it out as a piece of early ecclesiastical craft rather than mere building material. A ringed cross, sometimes called a Celtic cross in popular usage, is distinguished by the circle connecting the arms, a form with deep roots in early Irish Christianity and one that appears across carved stonework from the early medieval period onward.

The slab is made of granite, a material that weathers slowly and holds carved detail well over centuries, which may account for how clearly its features survive. It now stands displayed within the chapter house, a room traditionally used by cathedral clergy for meetings and administrative business, situating the stone in a domestic ecclesiastical setting rather than out in the elements. Ferns itself was one of the most significant ecclesiastical centres in early medieval Leinster, home to a monastery associated with Saint Mogue, also known as Áedán of Ferns, and later the site of a cathedral established after the Norman arrival in Ireland. The cross-slab fits into this long layering of religious activity on the same ground, though the notes do not specify its precise date or original location within the site.