Archaeologists have stumbled upon evidence that there was a gold trade route during the Bronze Age more than 4,000 years ago in what is now southwest Britain and Ireland.

Scientists measured chemical composition of some of the oldest known gold artifacts in Ireland to find that they were actually important from Cornwall in Britain — something that lead author Chris Standish of the University of Southampton said was an “unexpected” find that suggests Bronze Age gold workers in Ireland were using material from outside the country as far back as 2500 BC, according to a report by The Statesman.

Standish and his colleagues used laser abiation mass spectrometry to examine about 50 gold pieces from the Bronze Age from collections at the National Museum of Ireland. These artifacts included such things as necklaces, basket ornaments, and discs.

They were able to use this technique to measure the isotopes of lead, as well as compare them with the composition of gold deposits that were found in multiple locations. Using this process, they determined that the gold probably came from Cornwall and not Ireland, and therefore must have been traded as part of the tin mining industry.

While the Irish probably knew how to extra gold, they probably liked the idea of it coming from an “exotic” location, which greatly increased the value of gold and explained why they liked to import it, Standish said according to a UPI report. He noted that Ireland had plenty of easily accessible gold deposits found locally.

And it appears Britain didn’t value the gold as much as Ireland did, as there was more gold circulation throughout Ireland back then than was found in all of Britain. It indicates there was no universal value of gold during the Bronze Age, and there may not have been until gold coins started to appear a couple thousand years later.

Their findings were published in the journal Proceedings of the Prehistoric Society.