It is a small, carefully made object, tapering from roughly 37 centimetres at the top to 29 centimetres at the base, and its decoration has survived in raised relief: a four-armed cross whose each arm ends in a trefoil, that three-lobed form familiar from medieval ecclesiastical carving, with a matching trefoil terminal at the foot of the shaft. The top edge carries a fine raised moulding, and the sides are chamfered, angled outward in a way that gives the slab a subtle architectural quality, as though it were designed to be read in three dimensions rather than simply laid flat and forgotten.

The slab itself is thought to date stylistically to the 13th or 14th century, which makes it older than the chapel that now houses it. According to the historian William Carrigan, writing in 1905, the north chapel was added to the church by the MacGillapatrick family, also recorded as Kilpatrick, sometime in the 15th or early 16th century. The MacGillapatricks were a Gaelic Irish dynasty with deep roots in Ossory, the ancient territory that corresponds broadly to modern Kilkenny and Laois, and their attachment to this site is reflected in the choice to build a private family chapel within an existing ecclesiastical complex. The graveslab, predating that chapel by at least a century, was presumably moved or incorporated when the new structure went up, its carved cross and precise stonework still legible after all that displacement.