This is an authentic ancient Roman silver coin featuring Postumus, a ruler during the Roman Imperial era (27 BC-476 AD). The denomination is an Antoninianus and it was minted in what is now France. The year of production is believed to be 260 - 269 AD, making it an ancient artifact from over 1,700 years ago.

This is a valuable addition to any coin collection with historical significance and a connection to the Roman Empire.