At Castledermot in County Kildare, a small granite slab sits with a peculiarity that sets it apart from the more familiar carved stonework of early Christian Ireland: a deliberate hole, bored clean through the rock in an hourglass shape, roughly nine centimetres across at its narrowest point. This is not damage or weathering. The perforation was made intentionally, and its precise hourglass profile, wider at each face and pinched in the middle, suggests considerable care in the making.

The slab itself is modest in scale, standing 77 centimetres tall, 36 centimetres wide, and 17 centimetres thick. Cut from granite, the local stone of much of this part of Kildare, it carries an incised ringed cross, the kind of cross design common in early medieval Irish stonework where a circle connects the four arms, dividing the face into sections. Here those sections take a trapezoidal form, four panels that taper slightly rather than sitting as neat squares. Cross-slabs of this general type were produced across Ireland during the early Christian period, often marking graves or significant locations within monastic enclosures. Castledermot itself was the site of an important early monastery, and carved stonework survives there in some quantity, including high crosses of considerable sophistication. This slab is quieter and less celebrated than those, but the hourglass perforation gives it a character of its own. Such openings in carved stones are sometimes associated with oath-taking or healing rituals, with people passing objects, or even limbs, through the hole as part of a devotional or legal act, though the specific meaning attached to this particular example is not recorded.