An ancient route between Britain and Ireland supported a gold trade as far back as the early Bronze Age. Archaeologists in England say the trading of gold among the people of the British Isles dates back to 2,500 B.C.

The revelation is largely thanks to a new identification technique, which uses chemical signatures to trace the origins of gold artifacts. The measuring technique suggests some of Ireland's oldest gold artifacts are forged from foreign gold -- ores sourced from Cornwall, England.

"This is an unexpected and particularly interesting result as it suggests that Bronze Age gold workers in Ireland were making artefacts out of material sourced from outside of the country, despite the existence of a number of easily-accessible and rich gold deposits found locally," Chris Standish, an archaeologist at the University of Southampton and lead author of a study on the early gold trade, explained in a press release.

"It is unlikely that knowledge of how to extract gold didn't exist in Ireland, as we see large scale exploitation of other metals," Standish said. "It is more probable that an 'exotic' origin was cherished as a key property of gold and was an important reason behind why it was imported for production."

The technique, called laser ablation mass spectrometry, uses the concentration of lead isotopes as a measuring stick. Lead concentrations in gold objects are compared to the varying levels of isotopes in the gold sourced from surrounding sites. The method helped scientists illuminate the history of some 50 early Bronze Age artifacts.

Researchers say more gold circulated throughout Ireland during the Bronze Age than was found in Britain, suggesting different societies placed varying levels of value on the precious metal.

"The results of this study are a fascinating finding. They show that there was no universal value of gold, at least until perhaps the first gold coins started to appear nearly two thousand years later," said Alistair Pike, co-author of the study, which was published in the latest issue of the Proceedings of Prehistoric History.

"Prehistoric economies were driven by factors more complex than the trade of commodities -- belief systems clearly played a major role."