At the medieval church at Portraine in County Dublin, a bullaun stone was recorded in 1992, located within the ground floor of the church tower. Today, it is no longer evident. The stone itself, if it was one, belongs to a category of early medieval object familiar across Ireland: a large rock, often granite, with one or more rounded depressions ground into its surface. These hollows were used for grinding or pounding, and bullaun stones are frequently associated with early ecclesiastical sites, where they sometimes acquired later folklore around healing or cursing. This one may or may not have survived to the present day in any recoverable form.

The identification was made cautiously. The 1992 report described the stone as a "possible" bullaun, which is a meaningful qualifier in archaeological recording. The church at Portraine, referenced in the Sites and Monuments Record as DU008-031001, is a medieval structure, and the presence of a bullaun within its tower would not have been unusual, since such stones were often incorporated into later buildings or left in situ as earlier, pre-Norman sacred landscapes were absorbed into Christian use. The record was compiled by Geraldine Stout and updated by Christine Baker, with the site entry uploaded in December 2014. By that point, whatever object had been noted more than two decades earlier had already disappeared from view.

Portraine sits on the northern edge of the Fingal peninsula, and the church ruin is accessible to those familiar with the area, though it is worth knowing in advance that the feature specifically described in the record is absent. There is nothing to see where the bullaun once may have been. That absence is itself part of what makes the record worth knowing about: it points to how readily even substantial stone objects can be moved, reused, buried, or simply overlooked in the course of ordinary activity around old buildings. Anyone visiting the site with an interest in early medieval stonework will find the church tower still standing, but should approach with the understanding that the archaeological record, in this case, documents something that has slipped out of sight.