Based on hieroglyphics and images of people smoking, archaeologists assumed that the Mayans used tobacco. In the hope of finding physical remains, the researchers examined the inside of a particular clay flask dating back to the year 700 AD. Analysis of the flask revealed the presence of nicotine, as well as a few products of nicotine oxidation.

The chemical analysis owes some of its success to a dirty container—because the inside of the flask was not cleaned, the nicotine residue remained uncontaminated. It also helped that the flask had a single purpose, and was not reused to hold multiple products. But the most important aid to this discovery was undoubtedly some Mayan writing on the container. Which roughly translated means: container for tobacco.