This stone was discovered during conservation work in the summer of 1949. Likely eighth- or ninth-century in date, it had been reused in the thirteenth century in the building of the east wall of the chapter house and placed near the south-east corner of the south transept. After its discovery, it was moved inside the abbey infirmary where it stood in a recess against the south wall. Around 2002, it was moved to the former vicarage coach-house where it is displayed in the site interpretation centre.

Made of stone from the Preseli Hills, the monument is a large roughly rectangular slab measuring approximately 188cm x 48cm x 25.5 cm displaying a deeply incised linear Latin ring cross. The cross has small roundels at the ends of each cross arm where they meet the enclosing ring (those on the horizontal cross arm are positioned on the ring, those on the vertical arm are just outside of it), in the centre of the cross, and at the bottom of the long cross arm. Owing to the simplicity of the monument, its possible former use may be difficult to ascribe.

(Sources: Dyfed Archaeological Trust Historic Environment Record, PRN 1221; Nancy Edwards, A Corpus of Early Medieval Inscribed Stones and Stone Sculpture in Wales, Vol. II: South-West Wales (Cardiff: University of Wales Press, 2007), p. 468)
A.N. Coward, RCAHMW, 16.10.2018