This seated archer appears to be different on the obverse of this iteration of what is otherwise essentially the same denomination of coin.
Yours is rather a worn example showing pitting and possible coin clipping harvesting.
This second coin appears to be rather better shape.
You assert yours is authentic which, since this is a forum to seek answers, I presume is in the form of a question.
And, with your indulgence, I have one too. Are both coins likely to be genuine and if so why is the obverse on the second one different on yours?
Parthian silver is fascinating stuff. An earlier king, Darius II whose father had obtained much of his of silver from tariffs on what is now Turkish territory, lost it to Alexander the Great, the Greek who used it to build a city, Alexandria and a vault to keep it, the Parthenon, an iconic, ancient Greek temple on the Athenian Acropolis in Athens, Greece. Built between 447 and 432 BC at the peak of the Athenian Empire, it is widely considered the pinnacle of Doric architecture and a universal symbol of Western civilization and democracy.
The Greek architecture built with Parthian silver inspired much of what became the best of Roman public buildings which in turn coloured its politics as they did much later the architecture and politics of Washington, USA.
Darius the Great generated the first great silver wealth by imposing a standardized tribute system across the satrapies of the Achaemenid Empire. Provinces containing modern-day Turkey, such as Lydia and Phrygia, paid these annual silver taxes.
According to Herodotus, the satrapy of Phrygia, covering central and western Turkey, paid 360 Babylonian talents, about 10,800 kg of silver annually.
Neighbouring Lydia provided a massive, unspecific surplus of wealth as the empire’s financial hub. In total, the Persian Empire collected roughly 7,740 Babylonian talents about 232,000 kg. of silver per year from all satrapies combined, including Babylonia, Egypt, and India.
Generations later these coins minted for a successor of a different Parthian dynasty represent remnants of that first great silver fortune or at least one of them does, perhaps both?
CRWW