Its home is an Office of Public Works depot in Athenry, Co. Galway, having spent centuries on the southern wall of St. Caimin's church on Inis Cealtra, the small island in Lough Derg known in English as Holy Island, Co. Clare. The stone is relatively modest in size, less than a metre tall and under forty centimetres wide, yet it is carefully made: the face is dressed smooth and carries a deeply incised Latin cross, its angles hollowed out to create a more elaborate outline, the whole resting on a trapezoidal base. Above the cross, cut into the stone and running upside down relative to a viewer standing before it, is a two-line inscription reading ORDOMAEL PATRAIC, with the letters OR marked by an overline, a scribal convention used in medieval manuscripts and inscriptions to indicate an abbreviation.

The scholar R. A. S. Macalister recorded the slab in 1916 to 1917, noting it on the south wall of the church and dating it to the twelfth century. The name Maelpatraic, which the inscription appears to render in an early form, is an Irish devotional name meaning servant or devotee of Patrick, common in the early medieval period. The stone remained associated with the monastic site on Inis Cealtra until the early 1980s, when it was brought to the mainland. In August 1982 it was exhibited in Mountshannon, the small Clare village that serves as the main departure point for the island, and was subsequently moved to the OPW depot in Athenry for safekeeping, where it has remained.