This is a bullaun, a type of stone bearing one or more cup-shaped depressions whose precise original purpose remains a matter of debate among archaeologists. They appear at early Christian sites across Ireland, and while some may have served as mortars for grinding, others became focal points for devotional practice, with the collected rainwater in their hollows held to have curative or protective properties. The stone here measures roughly 0.65 metres by 0.5 metres, with the depression itself running to about 0.35 metres by 0.27 metres, large enough to hold the palm of a hand with room to spare.

The church beside which it sits is known locally as Cill Ghobnait, a name that links it to Saint Gobnait, an early Irish saint associated with healing and with bees. A second bullaun has also been recorded on the same site, lying on the ground to the north-west of a leacht, which is a low commemorative cairn or platform of stones traditionally associated with prayer and the veneration of saints. The presence of two bullauns in close proximity, alongside a leacht, suggests this corner of the island functioned as a layered devotional landscape over a considerable period. The details recorded here draw on information provided by Dr J. Waddell, and the site appears in Paul Gosling's 1993 survey of the area.