There may not be a more distinctive, or visually-engaging coin than the Lydian stater. Introduced in the middle of the seventh century BCE, the stater was the first coinage system. He was the one to receive a government-backed insignia, securing its value as a means of trade.
After King Croesus converted to a then-groundbreaking bi-metallic minting process, the stater became the basis for nearly every coinage system to follow. So what made the stater so innovative?