This head may be a recursive face, which I define as a profiled face displaying duplicate sets of eyes typically sharing the same profile foreheads, noses and mouths - as if two faces were superimposed on the same part of the monolith at different scales. For more details on this kind of artwork please click here.

Below I show a graphic to clarify what I mean:

June 2022 note - my confidence that this face is artifically carved is made stronger because I now realise the entire monolith follows the "dual symbol" design (click here for details) which requires such a horizontally orientated pointed face to be present.