The newly discovered slab, thought to date to around the 8th century, is small, roughly the size of a large hardback book at 54 centimetres long and 35 centimetres high, yet its carved face is densely considered. At its centre sits a cross-of-arcs design, a form in which the arms of the cross are defined by curved rather than straight lines, producing something that also reads as a cross pattée, where the arms widen toward their tips. The whole design is enclosed within a triple circle, with a small hollow at the very centre. The decorative logic behind such carvings is still debated; the cross-of-arcs may derive from the image of a cross surrounded by a laurel wreath, borrowed from Roman visual culture, or from the Chi-Rho monogram, the overlapping Greek letters X and P that formed one of the earliest symbols for Christ, rendered here within a circle.

The graveyard at Gallen has deep roots. The Early Christian monastery on the site was founded by St. Canoc in 492 AD, and Gallen Abbey, which stands at the centre of the present graveyard, developed near that original foundation. When excavations were carried out in 1934 and 1935 by Kendrick in a field to the north of the graveyard, they revealed a cluster of early medieval cross-slabs dating from the 8th to the 11th centuries, along with the remains of an early medieval church. Even before the recent find, eight cross-slabs of the cross-of-arcs type had been recorded from Gallen, as noted by Lionard in 1961, making it the single largest concentration of this design type known anywhere. The newly discovered slab brings that number to at least nine, and serves as a reminder that sites with long excavation histories can still yield unexpected material.

The slab itself is no longer at Gallen. It has been transferred to the National Museum of Ireland for safe keeping, where it is registered under the number 2022:118. A three-dimensional digital model of the carving is publicly accessible at skfb.ly/oxsXI, which allows a closer look at the shallow relief of the design than photographs alone tend to permit.