Cut into its western end is a circular bowl, roughly 23 centimetres across and 17 centimetres deep, of the kind known as a bullaun. Bullauns are deliberately carved depressions found in boulders and rock faces across Ireland, most commonly in early Christian monastic settings, and their precise original function remains a matter of some debate among archaeologists. They have been associated with grinding, with water collection, and with ritual use, and in many places they continued to hold significance in local folk tradition long after the monasteries around them had fallen into ruin.

This stone sits about 100 metres to the north-east of the church at the Drumacoo monastic complex, and according to information provided by Dr C. Cunniffe in 2011, it was incorporated into the boundary edge of a former roadway that once gave access to that church. The boulder itself is roughly triangular in plan, tapering from 65 centimetres wide at the western end to 50 centimetres at the eastern, and rising just 35 centimetres from the ground. Its modest dimensions make it easy to overlook, particularly now that the road it once edged has long since gone. What survives is a fragment of a whole landscape of movement and use, a stone that once helped mark the way to a place of worship, and that still bears the mark of hands that shaped it for purposes we can only partly reconstruct.