Two of them carried ogham inscriptions, an early medieval script consisting of lines and notches carved along the edge or face of a stone, used primarily to record personal names in an archaic form of Irish. The stones had not been carved as building material; they had been carved as monuments, then pressed into structural service underground, holding up a roof in the dark.

The stone in question is a sandstone pillar, subrectangular in section and measuring roughly 1.4 metres tall by 0.5 metres wide, narrowing slightly towards the top. It served as the north-east pillar of the souterrain, an underground stone-lined passage or chamber typically associated with early medieval settlement and used for storage or refuge. Its inscription, chiselled along the right angle of the stone and reading upwards, begins MAQI-TRENI AVI (T), a fragmentary formula meaning something along the lines of "son of Trenus, grandson of..." The remaining characters are lost or illegible. A companion stone, the south-west pillar, also carries an ogham inscription, suggesting that whoever built or modified the souterrain had access to more than one carved standing stone and repurposed them without apparent ceremony. The vowel notches on the north-east stone are notably worn, more so than would be expected from underground use alone, which points to the stone having spent a considerable period exposed to weather before it was taken and built into the structure, possibly centuries passing between its original erection and its second life as a roof support.