A fragment of a chest tomb, the kind of raised box-like monument that once marked the graves of the wealthy and well-connected in medieval and early modern Ireland, was dug up during excavations in 2015, and what survives of its inscription raises more questions than it answers. Carved in black letter script, the raised lettering reads only fragments: "…OR.C?" on one line, "UCREFU…" on the next. The rest is gone, broken off at some point before the stone was buried and forgotten.

The fragment is part of a mensa, the flat top slab of a chest tomb, cut from fossiliferous limestone, a stone dense with the compressed remains of ancient marine creatures, commonly used in the region during the medieval and post-medieval periods. It was found not in its original position but packed into 18th-century make-up material laid over the medieval floor level in the south transept and crossing of the church. That kind of secondary deposit is common in long-used ecclesiastical buildings, where earlier fabric gets repurposed as levelling or fill during later phases of construction or repair. St Mary's has a long and layered history as one of Kilkenny's principal parish churches, and the discovery during the 2015 excavation, documented by Cóilín Ó Drisceoil, suggests that this particular tomb had already been disturbed and displaced well before the dig. Who it commemorated, and when it was made, remains unknown. The partial letters offer no clear resolution, and no matching record has yet filled the gap.

The fragment is currently held in storage in the north-east corner of the south side of the graveyard at St Mary's, which is itself located in the Gardens area of Kilkenny city. It is not on display, and the inscription, tantalising as it is, remains unresolved.