I'm putting together a setting for a RPG campaign. The feel I am going for is Age of Englightment / Pirates of the Carribean (so, roughly 1730 technology level) but in an alternate world where humans compete with elves, dwarves, halfings and gnomes for resources on the planet (and those are just the "good/benign" races). Magic is used by a small percentage of the global population.
One culture/race is obsessed with gaining wealth through their large ocean-capable floating cities. Some members see value in controlling raw materials through legal ownership ("We own that distant mine and take our percentage"). Other members want to control services (manage an army that occupies someone else's mine or city; form a monopoly in one trade guild).
Those two are the minority, however; most of this population plans to profit through trade. Floating cities can transport large goods valuable to City A, small goods valuable to everyone, and perishables that have to be preserved. Dock a floating city near a large port, extend bridges, trade for a short season. All done, retract bridges, sail offshore; more security. These floating cities are very large (circular diameter of three miles); for shallow harbours they can build bridges or set up smaller trading floating trading posts that have a more shallow draft.
The population has much more knowledge and experience with economics than I do. (I'm willing to learn.) This race is known for the security of its banks and bank vaults, and for the trustworthiness of its citizens. There's enough infrastructure and trust between a set of nations for banks, loans and related financial tools to exist.
If this culture stamps its own coin, would it plan to put its currency in circulation with other races, cultures and nations? Would it try to keep all its currency internal and take in currency from other nations, and strongly limit where its currency went? Or would it make essentially no difference?