0 Euro - Sumatran rhinoceros

DNAB — a Dutch private entity, not a central bank — produces these zero-denomination souvenir notes legally because they carry no monetary value and therefore fall outside currency legislation. Oberthur Fiduciaire, one of the major security printers supplying genuine central banks across Africa and Asia, handles the production, which gives these collector pieces a build quality that far exceeds their nominal worth.

The Sumatran rhinoceros subject is a pointed choice: fewer than 80 individuals are estimated to survive, making it the most endangered rhinoceros species on the planet. Whether that urgency translates into long-term collector demand for the series remains to be seen.