In medieval times, wax seals weren't just a practical way to close an envelope—they were an important method of verifying your identity and showing that confidential letters hadn’t been tampered with. Like swiping a credit card or signing your name on a legal document today, medieval seals were used to close deals, bind agreements, and prove who you were. But while historians have long studied medieval letters and documents, they're only just starting to turn their attention to those documents’ wax seals.

According to Phys.org, a three-year study called Imprint—led by Philippa Hoskin from the University of London and Elizabeth New from Aberystwyth University—will examine wax seals from England and Wales dating from the 12th through 14th centuries. In order to learn more about the people who once handled these documents—including business contracts, land transactions, and financial deals—and medieval social structures, the experts will apply forensic analysis techniques like evaluating fingerprints and palm prints left on historic seals.

But they also hope the new information may help solve medieval crimes of fraud. For example, researchers will attempt to match up prints on suspected forgeries with prints on genuine documents.

“These wax seals have the potential to give us so much information about medieval people, but they are often set aside as less important than the document itself. This will be the first time that the information the handprints found on those seals will be examined, and it could really offer historians new understanding of the period,” Hoskin said.

[h/t: Phys.org, The History Blog]