10 Euros Auf dem Wasser

Germany's "collector euro" polymer ring series launched in 2016 with considerable skepticism from traditionalists — a plastic component in a legal tender coin struck at the Hamburg, Munich, Berlin, Stuttgart, and Karlsruhe mints simultaneously. "Auf dem Wasser" (On the Water) is the sixth installment, themed around climate and earth's natural systems. The polymer ring changes color depending on viewing angle, a security and novelty feature that also makes these coins essentially impossible to counterfeit at scale.

Each of the five German mints struck its own version, distinguished by mint mark, making a complete set of five a deliberate collector target.