To local tradition it is "Finn Mac Cool's Pebble", a casual projectile tossed by the mythological giant warrior as he strode through the midlands. To Catholic communities living under the Penal Laws, it was something altogether more urgent: a makeshift altar where Mass was said in secret, after the old chapel nearby had been burned.

The folklore surrounding the stone was gathered in 1934 from pupils at Turin National School and preserved in the Schools' Collection, a nationwide project that captured local oral traditions through children's accounts. One story describes Finn Mac Cool marching from Killucan past Edmonton towards Turin, stooping to pick up a rock blocking his path and throwing it two and a half miles, where it landed in a field beside Turin church and has remained ever since. A second account, collected from the same school, places the boulder at the centre of clandestine Catholic worship during the Penal era, a period from the late seventeenth century into the eighteenth when Catholic practice was suppressed under English law and priests risked transportation or execution. According to this account, Mass was said at the rock at midnight, while lookouts posted in the surrounding trees watched for soldiers arriving from Mullingar. The path the congregation used to reach the stone was still visible in the 1930s and was known as the "Mass Path". The notes from an Office of Public Works field inspection in 1967 describe the boulder as a natural formation, possibly fractured over time by weathering, situated near the eastern edge of a field. The landscape around it is notably layered: a ruined chapel site lies roughly 280 metres to the east, and two ringforts, the circular earthwork enclosures common across early medieval Ireland, sit within 140 metres to the west and north.

A bush visible in aerial photography is thought to mark the location of the mass rock today. The stone itself is unassuming, as such sites tend to be, and its dual identity, mythological curio and site of genuine devotional risk, is carried entirely in local memory rather than in any formal monument or signage.