Nobody knows where they came from. Their provenance is unknown, and it is apparent they were never meant to end up here; they almost certainly formed part of a much larger monument or commemorative architectural feature, now lost. The carving on each is heavily weathered, and each plaque follows the same format: a raised panel with a narrow border enclosing a shield carved in false relief, a technique that creates the visual impression of depth without actually cutting deeply into the stone.

The style of the carving and the shape of the shields point towards a sixteenth-century origin, consistent with what survives elsewhere in Galway from that period. Three of the plaques carry heraldic arms. The first bears impaled arms, meaning two coats-of-arms placed side by side on a single shield to represent a union of two families, tentatively identified as the French family on the right-hand side and a variant of the Lynch arms on the left, though those identifications are offered cautiously. The second carries a version of the Joyce family coat-of-arms, and the third shows what appears again to be the arms of the French family, flanked by the letters C and F. The fourth plaque is different in character: rather than heraldry, it displays a merchant's mark, the kind of personal device used by traders in place of a coat-of-arms. This one follows a type based on a reversed numeral 4, with crosslet terminals and an inverted V element, overlapped at the junction by a broken ring or annulet. Comparable merchant marks are recorded elsewhere in Galway, suggesting this was once part of a civic or commercial commemoration involving families of some standing in the late medieval town. The French, Lynch, and Joyce families were among the merchant dynasties that dominated Galway's trade and civic life during that era, which lends a certain coherence to the grouping, even if the precise original context remains a matter of speculation.