3 Marka Su-37 Berkut

Kaliningrad occupies a peculiar position in numismatic fiction — it is not a recognized issuing authority, and coins attributed to it fall squarely into the "fantasy issue" category, produced for the collector market rather than any actual monetary system. The Su-37 Berkut itself adds a layer of irony: the aircraft never entered serial production, making it doubly theoretical — a coin from a non-sovereign entity honoring a fighter that never flew in operational service.