Tetradrachm - Vologases IV

Vologases IV ruled for over four decades, making his reign one of the longest in Parthian history — yet his empire spent much of it hemorrhaging territory and prestige. Rome sacked Seleucia-on-the-Tigris in 165 AD under Lucius Verus, and the returning legions brought with them the Antonine Plague, which devastated both empires simultaneously. The Parthian mint at Seleucia continued striking through this period, though output and silver fineness declined visibly across the Sellwood 84 sequence.

Later issues in this type show increasingly debased fabric, a product of treasury pressure rather than any single reform.