That hollow, known as a bullaun, is the kind of feature found on early medieval stones across Ireland, thought to have been worn by repeated grinding, possibly for processing grain, pigment, or medicinal materials, though their precise purpose is still debated. What makes this particular stone quietly remarkable is not the bullaun itself but what lies beneath it: the boulder rests on a flat prostrate slab that once formed part of a megalithic structure, placing it in inadvertent conversation with a far older monument underneath.

The antiquarian T. J. Westropp recorded the stone in the early twentieth century, describing it in 1902 to 1904 as a sandstone block resting on a slab, roughly three feet by four feet, with a bullaun approximately thirteen inches across. The stone sits slightly off-centre to the south-east of a children's burial ground, a type of unconsecrated burial site used historically for unbaptised infants, known in Irish as a cillín. The boulder itself is irregular in shape, measuring roughly 0.75 metres east to west and 0.8 metres north to south. Its upper surface is triangular in plan, with a steep north-western face. The basin is oval, about 0.32 metres by 0.30 metres, deepest at the south at around 0.2 metres, and shallowing gradually towards the north-west, where it meets the edge of the stone with a gentle lip. The stone does not appear on any Ordnance Survey historic mapping, which suggests it either escaped the attention of early surveyors or was not considered significant enough to mark at the time.