This is the quiet puzzle at the centre of the Ballykean rock art record: a prehistoric carved stone, noted in detail by a Victorian geologist, that has since simply vanished from view.

The stone was first described by G. H. Kinahan in 1884, in what reads as a careful, methodical account. He identified it as stone L in his survey, describing it as a flat, irregular stone that slopes slightly towards the east, bearing seven cup marks. Cup marks are among the oldest forms of human mark-making found in Ireland, simple circular depressions ground or pecked into rock surfaces during the Neolithic or Bronze Age, their precise meaning still debated. Kinahan recorded the location clearly enough that a field inspection was carried out in 1990, following his coordinates, but the stone was not found. Whether it has been buried under shifting soil, removed, broken up, or was simply never relocated with enough precision to match Kinahan's original sighting, is unknown.