500 Francs CFA Brontosaurus

The BCEAO issues commemorative silver pieces under a licensing arrangement that has little to do with the monetary affairs of its eight member states — these coins are produced primarily for the collector export market, with distribution handled largely through European dealers. The "Brontosaurus" designation is itself an anachronism: the genus was formally synonymized with Apatosaurus in 1903, a status only reversed by a 2015 phylogenetic study, meaning this coin was struck during the thirty-year window when the name had no scientific standing whatsoever.