Clamshell Currency

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Scallops, conch shells and oysters accepted.
Money hasn't always been golden coins and paper bills. History has seen many, varied currencies, and seashells were very popular choices. Some are really beautiful and look valuable enough. Entire civilizations have used seashells as their currency, in many parts of the world, including Africa, Oceania and Asia. Notably, the use of cowry shells as money in China can be dated back three millennia. The Chinese character for "money" even is a pictograph of a cowrie shell!

These nacred currencies can be sometimes encountered in fiction, typically in sea-related tribes. After all, mollusks (animals that make the shells) live in water, and look very precious, and as such they can make excellent replacement for the typical golden cash.

A Subtrope to Weird Currency.

Examples:

Comic Strips

  • The characters in B.C. use clams as money. This is a literalized pun as "clam" was a standard slang term for "dollar" before the strip was created.

Literature

  • The titular Jokka from M.C.A. Hogarth's Tales of the Jokka use seashells as money, because they live in a landlocked wasteland separated from the nearest ocean by an impassable mountain range. Towards the end of The Worth of a Shell, the protagonists find a tunnel through the mountains and discover a beach covered with shells. Their initial thought is that they're rich, but then they realize that if they took all those shells back with them the economy would be ruined.

Tabletop Games

  • In Exalted, the marine settlements of the West use red cowry shells as currency (though, for portability's sake, they place them on strings).

Video Games

  • In Insaniquarium, the Fish Emporium seen in the Virtual Tank mode uses seashells as money, unlike the rest of the game, where regular money is used instead. Therefore, in this mode, the Guppies and other fishes drop shells instead of coins.
  • In Super Mario Odyssey, the area-specific currency in Bubblaine is purple scallops.
  • The Winterfin tribe in World of Warcraft values seashells above all other kinds of objects. So much that their currency is the Winterfin Clam.

Western Animation

  • In the BoJack Horseman episode "Fish Out of Water", BoJack tries shopping at an underwater convenience store that refuses to take his paper money and only accepts shells, prompting him to rob the store.
  • The Flintstones use whole clams, based on "clams" being slang for dollars at the time the show was made.
  • In the children's show Happy Ness: The Secret of the Loch, the nessies use seashells as currency.
  • In a song from the Schoolhouse Rock short "This for That" that deals with the money through the ages, the historical accuracy held by this trope is mentioned in this verse:
    Shiny shells were far more portable
    Why not use them for what's affordable?
    I'll give you this for that, that for this
    With shiny shells why barter?
    I'll give you this for that, that for this
    Shelling out shells is smarter!

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