In the 13th century, a merchant ship stocked full of ceramics, ivory, iron, and resin sank off the Indonesian island of Java. Some of the cargo likely originated from China, Vietnam, and Thailand, but the source of the fragrant resin—collected from plants and trees and used for perfumes, medical balms, and incense—has been a mystery. Using an NMR-based technique, Joseph B. Lambert and Allison Levy, both of Trinity University in San Antonio, determined that the resin may have originated in India or Japan. The team took carbon-13 and proton NMR spectra from samples of the shipwreck’s resin and compared the results with resin spectra from known locations as well as plant and tree sources. “At the time, resin could have come from a number of sources in Southeast Asia,” explained Lisa Niziolek, a researcher at the Field Museum, in Chicago, which houses some of the Java wreck artifacts. “Interestingly, the merchants themselves may not have known the true original source of the resin,” she said, because a lot of products were unloaded and redistributed at ports along this so-called maritime Silk Road trading route.