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 a cultural television channel from Mexico, there was a weekly recurring host panel of five or six academics in different fields, all with their PhDs in literature, linguistics, history, political science, etc. La Dichosa Palabra (The Blessed Word) was the name of the show.
Anyway, one of the panelists always seemed to trace the etymology of every word to the name of such-and-such goddess from antiquity.
One or two times, ok sure, you get dazzled by the erudition. But when it happens over and over and over again with any word no matter how seemingly trivial, it all acquires a strong whiff of confirmation bias bullshit with nobody to call him out on it.