When it came to scholarly attention in the late nineteenth century, it carried an inscription in a peculiar script that seemed to bear the Latin name "Margit". Comparisons were quickly drawn to a similar inscription carved on a cross at Carew in Pembrokeshire, Wales. The stone invited excitement, and for a time it was treated as a genuine early medieval survival, perhaps evidence of some transhistorical connection across the Irish Sea.

The excitement did not last. Writing in 1897, Vigors accepted the reading of the inscription, but doubts about its age were raised by Lynn in 1904 and 1905. The historian Orpen, examining the stone carefully in 1904, concluded that it was most likely a copy of the Welsh Carew inscription made sometime before 1863, produced by a hand familiar enough with the original to reproduce its unusual letterforms but not ancient enough to be what it appeared. A second inscribed stone, found at Baginbun, also in County Wexford, complicated the picture further. Orpen was inclined to view the Baginbun example as the older of the two Irish copies, and perhaps a somewhat more faithful one, though he stopped short of calling even that stone genuinely ancient. The probability, as the matter now stands, is that both Irish stones are nineteenth century reproductions of the Welsh original, made during an era when antiquarian enthusiasm and occasional creative licence were difficult to disentangle. The Fethard Castle stone, whichever hand made it and whatever its true age, is in any case now lost.