My guess is that the real crystal skulls were created by an ancient unknown civilization. We will not dwell here on the explanation of why I think so, but we will take it as a guess.
Why would an unknown and developed civilization make some kind of crystal skulls, and even give them to primitive people? Although there is a controversial point, but whether this artifact was intended for people.
While thinking, I really liked one version, for which I wrote this article. Imagine a situation if a highly developed civilization wanted to contact people for some reason, but could not be near them. They did not want to give the primitive Indians their technology for communication, but the problem must be solved.
This is how crystal skulls could have appeared. They could serve as simple devices for communication with the gods. Perhaps, for their correct operation, additional equipment was required, like some kind of altar or stand.
The creation of such artifacts solved several problems at once. The gods could communicate beautifully and effectively with humans, without giving them their technology. I do not exclude more exotic options that some telepathic or other abilities could be used for communication.
Many may doubt my words, since the skulls were thoroughly examined very recently and were found to be fakes, but who can prove the authenticity of the skulls sent? They could safely send fakes for research, and hide and study the real skulls.
The world is much more complicated than it seems at first glance, so you should never exclude the most fantastic versions.
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