The Incas may have used metal parabolic dishes to focus the sun in order to cut the blocks precisely. They employed those principles also to smooth and glaze the rocks. This theory rings true and loudly!

https://www.latimes.com/archives/la-xpm-1986-06-15-mn-11299-story.html

Hard for me to believe this guy is in my age group, but he has some pretty good jokes!

“Trillions of dollars [In the United States] were handed out to the mass of people. Checks were sent, remember? Many of you got them. Checks were sent out to businesses, to individuals on a massive scale. That’s not capitalism, friends. That’s the government saving us. And do you know what it’s saving us from? What would have happened in a pandemic if we had allowed regular capitalism to function! But we didn’t. So please understand – if things didn’t go even worse during the pandemic than they did, it’s because we kissed capitalism goodbye and started distributing money to masses of people so they could keep going. Turns out that works. It works pretty well, even in a pandemic. Maybe we ought to think about it under other circumstances…” (08:25) Richard D. Wolff