What makes it quietly arresting is precisely its incompleteness: the design was apparently abandoned partway through, leaving a cross-form that exists more as intention than execution, caught somewhere between raw material and finished monument.

The slab is rough slate, about 97 centimetres tall, with a straight top and a roughly pointed base. Whoever worked it cut two horizontal grooves, the upper one gently curving, joined to a central vertical groove, with pairs of opposed notches cut into the edges of the slab at either side. The overall effect is a cross-shape achieved through incision and notching rather than carving in relief, a technique seen on a number of early medieval Irish cross-slabs, where the symbol is suggested by the negative space of the cuts rather than built up from the stone. The design, though, seems to stop before completion, the grooves falling short of what the full scheme would presumably have been. What is particularly telling about this slab's history is where it ended up: at some point it was repurposed entirely, laid flat and used as a covering stone over the drain of a circular stone house on the island. A devotional object, or at least a stone in the process of becoming one, recycled as infrastructure.