>>96339863 (OP)
From civil war onward it depends on the edition.
Up until then, it's fairly consistent.
Essentially the native American tribes were using magic from (debateably) different sources to accomplish all kinds of wonders up until the 1300s or so. Magics and mundane were just freely mixed together in North America, however, most magical related shit sat firmly on the evil, comically evil, side of the fence. Not all, but you are talking around a 90% majority of the magical stuff being baby eating monsters levels of wicked. Some Injun shamans made the call to just seal away the magical side of things because, as handy as magic was, the net outcome was humanity just being collective prey animals to nefarious beings. Magic could still be accessed but it took a fuck ton of work, complex rituals, and had frankly trivial effects.
Then the Europeans rolled up essentially right after the natives blasted themselves back to the stone age and the events played out like real life history for the most part.
Some uber-injun shaman got all butthurt over losing around the civil war and threw open the gates to the magical realm again in California. This action was felt as a fuck huge earthquake. The earthquake unearthed Ghost Rock, a new resource that could be used in place of coal but "burns much hotter and much longer" with the side effect of the GR screaming when burned. The exact power capacity is never written anywhere, but it's used for intellstellar travel and nukes and shit in different editions, so just assume it's a "metric fuckton" of energy potential per rock and it powers all the sci-fi elements.
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