Ogham is an early medieval script, typically carved as a series of notches and strokes along the edge of a stone, and its presence here, broken and repurposed, tells a small but pointed story about what gets lost when the value of the past goes unrecognised.

The graveyard at Greenhill occupies a small hillock in a north-south valley, its modest dimensions, roughly 33 metres east to west and 22 metres north to south, enclosing the remains of a church set towards the northern portion of the site. The Ordnance Survey's first edition six-inch map of 1839 shows no physical boundary around the church at all, only a dashed line indicating an informal enclosure. At some point before 1874, a wall was built. It was during this work that the trouble began. Writing between 1874 and 1879, a scholar named Moore recorded that an ogham stone had been uncovered nearby and brought into the churchyard, but that the labourers engaged in enclosing the burial ground, unaware of what they had found, broke it apart. One fragment was then set into the wall as a quoin stone at the north angle, where it presumably remains to this day. A further possible ogham stone was later found in an adjacent outhouse, suggesting the area may have had more than one such carved stone in its vicinity.

The graveyard is described as maintained and in good condition. For anyone visiting, the north angle of the enclosing wall is worth a close look, where the built fabric of the nineteenth century and something considerably older have been, without ceremony, made into the same thing.