The stone, about two metres along its longest axis, sits by the north bank of the watercourse, its upper surface sloping away to the south-west. What makes it unusual is not simply its age but the density and variety of the marks left on it, a mixture of isolated carvings and a more elaborate composed design, all worked into a surface that has spent an unknown length of time in and out of flowing water.

The carving was identified and described by Aoibheann Lambe, who recorded eight isolated cupmarks across the surface, each roughly four centimetres in diameter. Cupmarks are among the oldest forms of human mark-making found in Ireland, simple circular depressions ground or pecked into stone, whose precise purpose remains unknown. Alongside these sits a more involved composition: three clearly defined cupmarks enclosed within a sub-oval ring measuring approximately thirty centimetres across, a form known as cup-and-ring art. A further single cupmark and two fainter impressions appear on the ring itself toward the south-west. Most strikingly, the groove forming the south-western side of the ring does not stop at the ring's edge but continues diagonally eastward all the way to the boulder's edge. Running parallel to it, five centimetres below, is a second groove, accompanied by two more cupmarks. The effect is of a design that refuses to be contained, lines escaping their own composition and travelling toward the stone's boundary.

The boulder's position in an active stream means conditions on the ground will vary considerably depending on water levels, and the finer details of the carving, particularly the fainter cupmarks, are likely to be most legible when the surface is neither flooded nor obscured by vegetation. The stone's orientation, with its long axis running north-east to south-west, matches the direction of several of its carved grooves, though whether that correspondence was intentional is one of the many questions this kind of rock art tends to leave open.