The color seems to have been paint, from what I've read so far, but I can't recall how they created the color they used the most on buildings. I do remember being very interested reading about it originally years ago. Wish I could. They also painted a lot of colors on their amazing murals throughout the Americas. Some groups even created elaborate pictures using the bright feathers of tropical birds. They should have waited until the birds shed them molting!
I think in certain situations, they also used a lot of white paint. as I read when the Spanish invaders first approached the coast of Mexico, at one location, they could see many white buildings shining brightly in the daylight, and were astonished, as they all presumed, as Europeans always did that the people they intended to conquer and use were all brainless idiots. Some of the Spanish who kept journals described the citizens they discovered in the Caribbean as being like children. Right. (They hadn't made sneakiness, selfishness, aggression, and duplicity the foundation of their daily lives, of course, like the invaders! )
The architecture throughout the Americas, from the Southern tip northward was incredible. It was intelligent, extremely advanced, and has never been given the respect it truly deserves by Western clowns even yet. The racism toward the actual citizens of the "New World" seems overpowering, and blindingly stupid. It has prevented honest respect from developing which should have been there from the first.
I can't wait until they finally make enough progress in science to start the real discovery of what has been buried by time and the elements since super-prehistoric ancient times.
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