Phase 4: engravings
The groupings of phase 4 are more contentious, in part due to a lack of direct contact between phases previously described and an arrangement of grooves that do not conform to the same pattern, with fewer interconnections between grooves. Three sub-phases and two additional sub-phases linked to one of these sub-phases are evident, but the phasing of the piece here becomes ambiguous. It could be that phase 4 follows phase 3, occupying one of the few vacant areas left on the surface, or it could be the exact opposite, actually representing the earliest phase, with those phases already described engraved at a later time. These possibilities are explored in greater detail in the phasing summary below.
Phase 4a
Sub-phase 4a consists of three grooves engraved from 'north' to 'south'. These grooves have been grouped based on direction of working, orientation and the similarity in profile shape. The far 'western' groove in this sub-phase looks to be cut by grooves associated with sub-phase 4b, described in greater detail later on, suggesting 4a may be an older component of phase 4. Significantly, an otherwise anomalous set of two possible grooves may be associated with phase 4a, based on their orientation. However, the spatial dislocation of these grooves, as well as the dissimilarity in profile size and shape makes such an association highly tentative. If they are associated, this would be highly significant as it would potentially offer a way to directly link and order phases 3 and 4. However, the relationship between these grooves and sub-phase 3b1 could not be discerned.