Tetrobol

Selymbria occupied a strategically awkward position on the northern shore of the Propontis — close enough to Byzantium to be perpetually in its shadow, yet independent enough to strike its own silver throughout the early fifth century. The city sided with the Delian League after the Persian Wars but maintained a distinct civic identity, and its coinage reflects that brief window of autonomy before larger powers progressively absorbed the region's monetary output.

The HGC 3.2 reference places this type among a small, tightly clustered group of issues, none abundant in the market.