The tiny coin, smaller than a fingernail and minted from almost pure gold, features the portrait of Queen Berenice II of Egypt’s Ptolemaic Kingdom.

The discovery was made in the City of David, an archaeological site considered to be the most ancient part of Jerusalem. It is a remarkable find, being the first of its kind ever discovered outside of Egypt. Only 17 other such coins are known to exist worldwide, BBC reports.

Minted in the Egyptian city of Alexandria approximately 2,270 years ago, the coin depicts Queen Berenice II, who was married to Ptolemy III, a ruler of the Greek-led kingdom in Egypt from 246 to 221 BC. One side shows the queen wearing a tiara and veil, while the reverse features a cornucopia – the ‘horn of plenty’ – flanked by two stars. The ancient Greek inscription “of the Queen” suggests Berenice may have ruled while her husband was away fighting the Third Syrian War. Experts believe the coin could have been a special reward for soldiers who fought in that conflict.

The find challenges previous assumptions about ancient Jerusalem’s status. “The golden coin we found here tells us that Jerusalem was an important city,” said Professor Yuval Gadot, the excavation director. The discovery suggests the city was a richer and more integral part of the Ptolemaic Kingdom than previously thought.

Archaeologist Rivka Langler discovered the treasure while sifting soil at the Givati Parking Lot excavation site. “At first, I couldn’t believe what I was seeing,” she said. “But within seconds I was running excitedly through the excavation site.”

Dr Robert Kool, head of the numismatics department at the Israel Antiquities Authority, described it as a “gorgeous coin”, emphasising its unique significance as the only specimen found beyond the Ptolemaic centre of rule in Egypt.