Despite their name, the coins did not appear to be Assassin in origin. Inscribed upon their rims were the words Hispaniarum Rex—Latin for 'King of the Spanish'—hinting at a Spanish source, but they were marked by uncanny anachronisms. First, the year was given as 1788, almost two decades after they first arrived in New Orleans around 1769, but even stranger was the symbol on their faces—the telltale triangular insignia was the logo of Abstergo Industries, the Templar corporation which would not be founded until 1937. If not for these mysterious traits, they would have appeared to be relatively ordinary silver coins.
The mysterious coins had reached New Orleans and the Louisiana Bayou in the pockets of smugglers by 1769. The Assassin Aveline de Grandpré subsequently seized all ten of them from the smugglers by force, seven of whom she encountered in New Orleans and the other three in the Bayou. While useless as money, she was able to exchange them at a tailor's shop for the Bayou Hunter outfit.
Behind the scenes
The Assassin's coins are one of three persona-specific collectibles in Assassin's Creed III: Liberation. As their name suggests, they can only be collected when the player character, Aveline de Grandpré, is dressed in her Assassin persona because only then will the ten smugglers who carry them appear. To retrieve the coins from them, they must be either killed or knocked out and looted.
Ironic given their name, the coins feature the logo of Abstergo Industries which would not be founded for centuries after the era the game takes place. Assassin's Creed III: Liberation within the series' universe is itself a video game produced by Abstergo Industries under the same name which has been edited for censorship. One possible in-universe explanation is that the logo in the coins are a result of the company's editing and are not faithful to their design as encountered by Aveline de Grandpré.