20 Francs Dunkleosteus

The Democratic Republic of the Congo has issued commemorative silver under its own authority since the post-Mobutu reorganization of 1997, and by the 2020s had built one of the more prolific novelty bullion programs among African sovereign mints — with virtually no domestic circulation component. These coins are struck entirely for the international collector market, typically through European minting contractors.

Dunkleosteus terrelli, the armored placoderm this coin commemorates, patrolled Late Devonian seas roughly 360–380 million years ago and reached estimated lengths of six meters. It had no true teeth — its jaws were formed from self-sharpening bladed bone plates capable of generating bite forces estimated by researchers at over 4,500 newtons.