Wow, of all the amazing luck! I just met a visitor from a magical world. He was able to use his magic to establish common communication, and after a bit of talk he decided he wanted to bring some stuff from my world back with him, so we worked out a deal.

I went shopping and purchased a few hundred dollars worth of various goods, and he gave me a rather large pouch of gold coins in return, then departed. With the price of gold being what it is, I'm rich!

...maybe. The thing is, these are *coins*. Disks of what appears to be an alloy of reasonably high gold content, stamped with the image of some guy who I assume is a king on my visitor's world, and a bunch of what appears to be writing in some script I've never seen before. If I try to sell these to a gold dealer or a coin broker, it will almost certainly invite questions that I don't want to answer! Of course, I could always try the black market, if I knew how to find such an institution, but I'm a reasonably law-abiding citizen and I'd prefer not to have to deal with criminals. (Besides, even if I didn't get them stolen outright, I've heard that you tend to get a lot of the price taken out as various underworld-security fees, and I don't want that; I want to be rich!)

What strategy would allow me to turn the gold coins into the maximum amount of dollars with a minimal level of risk of anyone asking questions about where they came from?


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Example (to demonstrate that question is not specifically about character action):

Two countries come into contact for the first time. Country A uses fiat dollars, country B gold coins. People from country A are unfamiliar with country B's coins. Recently country A has had an influx of tourists from country B who try to buy things with gold coins. When a merchant in country A sells goods or services to a tourist from country B, how would he go about exchanging the gold coins he receives for dollars?