It is either an anchor or an anchor combined with a cross, the distinction being genuinely uncertain, and that ambiguity is part of what makes it interesting. The motif is not small: the grooved design runs to just over half a metre in length, with the arm or transom spanning 22 centimetres across and the full width between the two anchor points reaching 38 centimetres. It fills much of the usable face of the stone.

The carving has been executed with evident care. Whoever made it took the trouble to prepare the surface first, and the lines themselves are deliberate and controlled. The transom ends splay outward, the U-shaped base of the anchor curves gently and extends slightly beyond the tangs, and the top of the shaft carries a loop on its right side. That loop is the most puzzling detail. It may be a residual trace of the Chi-Rho monogram, one of the earliest Christian symbols combining the Greek letters X and P as an abbreviation of the name of Christ, which sometimes appeared alongside or merged with anchor imagery in early Christian contexts. The anchor itself was an established symbol in early Christianity, drawn from a passage in the Epistle to the Hebrews and used widely in the catacombs, where it stood in for the cross during periods of persecution. Whether the Cregganna More carving represents a late survival of that tradition, a local adaptation, or something else remains open. What is clear, as researchers have noted, is that this is not casual scratching. The intentionality of the work is legible in the stone itself.