Oddly enough, this means that these ancient human tools could very well have been scooped up, polished, sold, and incorporated into private collections of semi-precious stones, without their collectors realising they had actually nabbed ancient artifacts. Those aren't … So the Calico site basically stands exactly on this weird dilemma, where the distinction between a mere rock and an artificially shaped tool takes on an importance it might not otherwise seem to have. …

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A Visit To The Weirdest Archaeological Site In North America …