The structure measures roughly 2.4 metres by 2.55 metres across, with the capstone standing about 0.61 metres above the ground. That arrangement, a substantial slab raised clear of the earth on a cluster of uprights, is what archaeologists classify as a boulder-burial, a Bronze Age monument type found mostly in the south-west of Ireland and thought to mark individual interments beneath or around the capstone.

What makes this particular example quietly complicated is its local identity. The community around Cappaghavuckee knows it not as a prehistoric tomb but as a mass rock, the kind of improvised outdoor altar used by Catholic priests during the Penal Laws of the seventeenth and eighteenth centuries, when public Catholic worship was suppressed and congregations gathered in remote spots to avoid detection. A Mass House recorded nearby suggests this corner of the hillside carried genuine religious significance in that later period, whether or not the boulder itself was ever used as an altar. It is entirely possible that a prominent, already-ancient stone structure drew people to the spot precisely because of its presence, and that the prehistoric and the penal-era uses became layered together in local memory until the older origin was largely forgotten.