The piece in question is the transom, or horizontal cross-arm, a sandstone bar measuring just under 80 centimetres in length, which once marked the head of a grave in the old monastic graveyard. It is not the full soaring shaft that the term "high cross" typically conjures, but the craftsmanship preserved in it is considerable. The hollowed angles at the crux are characteristic of the classic Irish high cross form, and around the edges runs a double moulding. Each face carries a carved figure: one is a bishop in vestments, holding a crozier; the other is interpreted as Christ performing a blessing, shown fully clothed with arms extended from the elbows and palms turned outward. One end panel bears an intricate interlace design, the kind of tightly knotted geometric ornament associated with early medieval Irish stonework, and the opposite panel is thought to carry the same pattern, though wear has made it harder to read.

The cross-arm originally lay in the graveyard associated with an early monastery at Cloone, a site with roots deep in the early medieval period. It had been placed, perhaps deliberately, at the head of a grave, which may suggest it was already regarded as an object of some significance even after the cross itself had broken or been dismantled. In the early 1990s, when the small graveyard of St. Mary's underwent conservation work, the fragment was moved there for safekeeping, separating it from the monastic site where it had long rested. The scholarly treatment of the piece, including the identification of the figures and the dating of the ornamental style, draws on Kelly's 1993 analysis, which placed it within the broader tradition of Hiberno-Romanesque and early Christian stone carving in the region.