The vitrified examples under study come from famous Peruvian sites, in South America. Without testing, the debate is open to claims of unusual polishing techniques, natural degradation, lava flows and many other odd explanations. The analysis below eliminates some of these ideas.
The vitrified stones of Peru were first brought to popular attention by Erich von Daniken in the 1970s. He noted the vitrification at Sacsayhuaman in his book Chariots of the Gods.

Peruvian Alfredo Gamarra had identified this vitrification earlier. The identification and cataloging of these intriguing stones has been carried on by Alfredo’s son Jesus Gamara, and Jan Peter de Jong. In Sacsayhuaman, there are many other indications of the use of heat. Strange marks on the stones like the one pictured can be found; shiny, completely smooth and with another color to the rest of the rock.bren
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