May 9, 2023
Mineralogists and geologists from the University of Granada studied Maya ancient plasters in Honduras which have held up better than the plaster used in the Aztec empire. They have discovered the secret ingredient in that plaster. They used X-ray machines and electron microscopes and found organic material in the mix. They consulted masons and Maya people living near the site of Copan which led them to two trees, the chum and jilts and the sap from those trees.
They added the sap to plaster ingredients limestone and water which reacted to carbon dioxide in the air to make lime mortar. They mixed in the sap and found that this created a plaster impervious to the Honduran humidity.
Their research is published in Science Advances
Carlos Rodriguez-Navarro et al, Unveiling the secret of ancient Maya masons: Biomimetic lime plasters with plant extracts, Science Advances (2023). DOI: 10.1126/sciadv.adf6138
Physorg has the report here:
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