Reverse of a silver tetradrachm minted in Amphipolis during the reign of Alexander the Great. Zeus seating left on a throne, holding an eagle and a scepter. The tetradrachm was an Ancient Greek silver coin equivalent to four drachmae and it was in wide circulation from circa 510 to 38 BC. The tetradrachm's use as a currency was adopted by many other city-states of the ancient Greece, Asia Minor, Magna Grecia and other Greek colonial cities throughout the Mediterranean Sea. With the armies of Alexander the Great it spread to the Greek-influenced areas of present-day Iran and India.