Assarion - Domitian with countermark "helmeted bust of Athena"

The countermark on the coin, which features a helmeted bust of Athena, was added to the coin as a way to indicate that it was issued by the Roman province of Cilicia, specifically from the city of Flaviopolis. This practice of countermarking coins was common in the Roman Empire, as it allowed provinces to issue their own coins while still maintaining a standardized system of currency across the empire.