Among the more than 7,500 fragments from the Java Sea shipwreck that reside in Chicago’s Field Museum are corroded lumps of iron, exported from China for use as weapons or agricultural tools in Southeast Asia; button-like weights used on merchants’ scales; barnacle encrusted chunks of aromatic resin and crumbling ivory; and thousands upon thousands of ceramic wares. Each ancient object has its own history and context, but it was a tiny inscription on one that helped researchers unlock the mystery behind this wreck—or so they thought.
Etched on only two ceramic containers, the words “Jianning Fu” gave the lidded box a specific provenance. When anthropologist Lisa Niziolek first saw the writing in 2012, she realized that the city name only existed in that form for a brief window of time: “Fu” designated Jianning as a Southern Song dynasty superior prefecture beginning in 1162. By 1278, the city had changed to Jianning Lu, a new designation bestowed by the invading Mongol leader, Kublai Khan. That seemed to fit perfectly with the shipwreck’s initial date of mid-to-late 13th century.
This, Niziolek thought, was the smoking gun. “At first I was all excited that we were looking at this short time period,” she recalls. “We were thinking that it was just within a couple years of that [political] transition.” Narrowing down the shipwreck’s age to such a short range of dates might’ve indicated that this boat sailed during the uneasy transition years between the Song and Yuan dynasties.
But once she began conferring with colleagues in China and Japan about the types of ceramic she was seeing in the collection, she started having doubts. Tantalizing inscription aside, the other experts thought the ceramics more closely matched the style of earlier objects. Archaeologists who first assessed the wreck in the 1990s sent a single sample of resin for radiocarbon analysis, which provided the date range of 1215 to 1405. “It can be said with some certainty that the ceramics cargo does not predate the thirteenth century,” those researchers concluded.
Science is about putting forth a hypothesis, comparing it to the available data, and adjusting it accordingly. So Niziolek and her team decided to submit three more samples for radiocarbon analysis, two from the resin and one from the ivory. Thanks to technological advancements, labs now use accelerated mass spectrometry, a technique that requires smaller sample sizes and provides more precise results than the earlier