Mexico City, August 18 : Archaeologists have gathered the earliest evidence of tar used as waterproofing material in Veracruz in Mexico, which is more than 3,500 years old.
Earliest remains of containers with tar are those recovered in the municipality of Hidalgotitlan, Veracruz, as part of El Manati archaeological project.
Olmeca cultures that inhabited the Gulf of Mexico vicinity used tar to protect soil, terracotta or wooden constructions, floor and wall covering, boat sealant, as well as glue.
According to University of Pennsylvania archaeologist Carl Wendt investigations, Olmeca people collected tar directly from deposits, many of them concentrated at Eastern Veracruz, between Coatzacoalcos and Choapa rivers.
Once collected, it was transported to the dwelling areas, where it was warmed up and combined with other materials like sand and vegetal elements to harden it.
Contemporary inhabitants of the Gulf coast vicinity still use tar to flatten the entrance of their houses, patios, floors and highways, but mainly to fix boats, as their ancestors did more than two thousand years ago.
In December 2007, in the right margin of Coatzacoalcos River, two Cayucos were found.
This finding represented archaeological confirmation regarding the use of tar, or chapopote, as waterproofing and sealant material, which is at least 2,500 years old. Although the wood has disappeared, the tar coating remains.
Alfredo Delgado, man in charge of INAH archaeological project, explained that the ships' vestiges confirm that the use of a waterproofing and sealing is a millenary technique.
Cayucos' rests consist of several thin tar layers that vary among 1 and 7 mm depth.