When the historian William Carrigan recorded it in 1905, he found it in Mrs Carroll's field, roughly 228 metres south of the graveyard, and he described it as a font, a vessel for holy water. It is neither where he found it nor what he thought it was. The stone has since been moved inside the graveyard boundary, and the field where he located it is now empty. What Carrigan took for a font is in fact a bullaun stone, a type of ancient carved rock bearing one or more deliberately hollowed depressions whose precise ritual or practical purpose remains a matter of quiet scholarly debate.

The site at Killamery has a long religious history behind it. According to Carrigan, a monastery was founded here by St. Gobán Fionn in the early seventh century, and the community was evidently still active centuries later; the Annals of the Four Masters records the death of an abbot named Domhnall, son of Niall, in 1004. What survives from that monastic period is a scattered but legible collection of stonework, including a high cross, two cross-slabs, a stone cross, church remains, and two bullaun stones, all now enclosed within the graveyard on raised ground that looks out over a broad plain to the north and west. The bullaun in question is a free-standing old red sandstone boulder, roughly 84 by 68 centimetres across, with a roughly circular depression about 33 centimetres wide and 18 centimetres deep. At some point, half of the stone's upper surface broke away, leaving one side of the bowl shallower than the other. Ten metres or so to the south, in a small valley where the ground dips sharply away from the hillock, St. Nicholas's holy well sits quietly alongside the remains of the church, the whole complex compressed into a surprisingly small and uneven landscape.