A 5,000-year-old 'spider stone' found in the island of Bornholm in Denmark [1240x1277]
whats it for?
I think the most widely accepted interpretation is that it’s a depiction of the sun and that it’s related to Early Neolithic sun worship. It was found in relation to a large religious complex (Vasagård) so it’s pretty obvious to interpret it in that light. It’s not unique either. There are several of similar sunstones from the area.
This doesn’t really apply to your answer since it makes sense with other sunstones and the location of it but I love how that’s almost always the assumption when we find something old we have no answer for. “Probably for religious or spiritual purposes” hehe.
Spoiler for Horizon Zero Dawn. For those who don't know the game, the basic premise of the game is that you're 1000 years post total apocalypse caused by AI controlled military robots.
Your comment reminds me of a side quest to find old mugs for an archeologist. The mugs have various logos on them, as mugs often do, and instead of thinking they're just mugs with designs on them, the archeologist presumes it's for religious or spiritual purposes, possibly a beard shaving ritual as a coming of age for young men.