Heliopolis' royal influence began during the second dynasty, it seems possible that all kings from Djoser on (those who built pyramids) built shrines or chapels in or near the Temple of Atum (Kahl). Pyramids are the direct result of royal solar cult afterlife doctrine and are associated with the ben-ben stone fetish of Heliopolis (Lehner), remarkably the apex stone forming the pyramids top (its capstone) was called the ben-ben-et (Sahure causeway: relief of king in procession bringing his pyramid's 'ben-ben-et' to be placed on its top).

Circumstantially we can deduce the ben-ben-et was crafted, engraved and ceremoniously consecrated in the Temple of Atum; when finished it was brought in grand procession to be placed atop the king's pyramid. In this context I suggest we should view the ben-ben as being 'the' Ka stone of Re and the ben-ben-et as a symbolic replication or duplicate ben-ben... intended to be the king's Ka stone, after all the king couldn't use/occupy his father's ben-ben during his daily rise above the eastern horizon - he needed to have his own.

B.A.Hokom