Rather than the crosses, effigies, or inscribed lettering common to medieval funerary stonework, this slab carries something far more spare: two diagonal lines running from corner to corner, meeting at a single cup-mark, a shallow circular depression pecked into the stone at the point where the lines intersect.

The slab itself is described in the record compiled by Geraldine Stout, drawing on earlier documentation by Ó hÉailidhe and Prendergast from 1977 and a later publication edited by K. Swords in 2009. It is a relatively modest piece of stone, just over a metre long and tapering towards one end, measuring 1.02 metres in length, 0.40 metres in width, and 0.09 metres thick. It sits attached to the exterior of the chancel near the south wall of the church, recorded under the site reference DU022-030001. Cup-marks, which are among the oldest forms of carved mark found on stone in Ireland, typically consist of these small circular hollows ground or pecked into a surface; their precise meaning remains a matter of ongoing discussion among archaeologists, though they appear across a wide range of contexts from prehistoric rock art to ecclesiastical stonework. Whether their presence here is incidental, symbolic, or the result of later reworking is not recorded.

The church at Whitechurch sits in the foothills of the Dublin Mountains, south of the city, in an area with a notable density of early medieval and later ecclesiastical remains. The slab is not displayed or interpreted on site in any formal way, so visitors should look carefully along the south-facing exterior wall of the chancel, where it is set flush against the stonework. The incised lines are described as deeply cut, which should make them legible even in flat light, though a slightly raking light from the side will always bring carved surfaces into sharper relief.