Also mistaken for fulgurite by the more naturalistically minded, apparently. Maybe most common in the Nordics, based on viking references?
Additional links:
https://www.nationalgeographic.com/science/article/100810-thor-thors-hammer-viking-graves-thunderstones-science
https://fi.wikipedia.org/wiki/Ukonvaaja [Finnish]
On the last part, you can see Jesuit exorcism markings on Tiwanaku and Inka statues. They tried to tear down temples too, but couldn’t figure out how to dismantle the foundations and first meter and a half off walls. So they used those to build European style dwellings on top of it.