That absence is itself the story. A dark-grey, slate-like cross-slab, measuring just over a metre in length, was recorded lying on top of the north wall of the cloister garth of the Augustinian Abbey, having been moved there from its earlier position underneath the garth wall itself. At some point after that, it disappeared entirely.

The slab carried an incised cross, a type of early medieval carving in which the design is cut directly into the stone surface rather than raised in relief. The cross on this slab was organised around a central circle, from which arms extended outward to terminate in expanded horseshoe shapes, with an outer incised line running parallel to an inner one on each side. The base and sides had already suffered damage and erosion by the time it was recorded. What makes this piece particularly interesting is the company it keeps in terms of style: comparable cross-slabs at Clonmacnoise in County Offaly and Cong in County Mayo have been dated to the 10th century, suggesting this slab may belong to roughly the same period, placing it among the earlier phases of activity on an island whose monastic history stretches back to the 7th century. The cross-slab was documented by M. Weaver in a 1995 architectural survey of the island, and it was already noted as missing by that point or shortly after.

Innisfallen is accessible by rowing boat from Ross Castle, and the ruined abbey remains a place worth visiting in its own right. But the cross-slab serves as a reminder that island sites, however visited, are also places of quiet attrition, where objects shift, deteriorate, and eventually vanish, leaving only measurements and descriptions behind.