It's also still out there that the Egyptians themselves actually inherited the tech from a yet older human civilization as well. I'm of a belief of the possibilities of major civilizations existing and then being destroyed by nature or artificial self means and practically deleting history as it cycles to the next civilization. Like the Incas who were clearly building on older foundations. Many races have built over preceding populations all over the world. It's kind of how we evolve. On the shoulders of the past.
Most moai are made of tuff. Tuff is a soft volcanic rock native to Easter Island. (A few moai were carved from basalt and scoria, other volcanic rocks.) Because tuff erodes easily, few of the moai's original designs remain. Moai that were buried retain some original markings, which are similar to Rapa Nui tattoos of the period. https://www.nationalgeographic.org/media/quarry-easter-island/
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