One of those hollows is V-shaped in section, an unusual profile that sets it apart from the more common rounded or hemispherical basins found on similar stones. This is a bullaun stone, a type of ancient carved or ground feature found across Ireland, typically consisting of one or more cup-shaped depressions in a boulder or outcrop. Their precise purpose remains a matter of debate among archaeologists, though they are variously associated with early Christian sites, ritual water-holding, and grinding. The Ballyhad example sits quietly in the landscape with no obvious ecclesiastical context nearby, which only deepens the question of why someone, at some point, worked this particular stone.

The stone was recorded by Liam Price, the Dublin judge and amateur archaeologist whose meticulous surveys of County Wicklow during the mid-twentieth century documented scores of monuments that might otherwise have gone unnoticed. His 1959 reference places this bullaun at catalogue number 12 in his listing of such features across the county. The boulder itself is earthfast, meaning it is embedded in the ground rather than freestanding, and the two basins are cut into its exposed upper surface. The granite is native to this part of Wicklow, a county underlain by a large igneous massif, so the raw material was hardly scarce. What remains striking is the effort involved in working granite at all, a particularly hard stone, and the deliberate shaping of one basin into that angular, V-shaped form rather than the rounded hollow that grinding or weathering alone might produce.