What do you do with foreign coinage that gets mixed in with your country's currency?

Currency is whatever we define it to be. It’s only “invalid” if one party attempts to use something other than what both parties have agreed to. If the shopkeeper accepts a pint of goat’s blood I give him in exchange for his goods, that’s not fraud. That’s an agreement between him and me. If he chooses to accept a Canadian Nickel in exchange for goods, that would be a similar agreement.

That being said, if the shop keeper does raise an objection to it, then it’s my responsibility to provide currency that he does accept, or else void the sale.

Most stores in the US will take Canadian coins. In fact, I bet most won’t even notice it. There are some shops in the southwest that will accept pesos, though probably not many.
I don’t come across foreign currecy often enough to have a set routine. I keep a few coins or bills wheneveb I go abroad, as a sort of collection. But if someone gives me a Canadian quarter a change, I’ll either spend it again or end up just getting rid of it.

I’m a coin collector, so if something is exotic, I pull it aside first off. But more often than not, living in the US in a state that borders Canada, when I do get foreign coins, they are Canadian. What’s unusual about Canada vs other countries is that their coinage is in the same denominations as ours, and each denomination is the same size, shape and color as ours. You’d think whomever designed their coins last would have thought of that.

But I remember pretty much from the time I started to collect coins, (which was the early 80s in my pre and early teen years), when my parents actually took me on a couple of road trips where we went through several Canadian provinces, I also knew about exchange rates, and Canadian money was ALWAYS worth 60 to 70 cents on the dollar to American money, and when you’d find a Canadian quarter, you’d actually feel like you’d been had, it was worth maybe 17 cents, not 25. But a nickel was still worth 3 or 4 cents, and rounding up, even @ a 60% exchange rate, a single penny was always still pretty much worth a penny, and I found that as a kid if I spent pocket change without looking at it, quarters would rarely be accepted, but no one paid much attention to pennies and nickels. And occassionally but FAR less rarely I’d encounter a Canadian dime, but those actually somehow look smaller…I think Canadian coins might be fractionally smaller than US coins, but the difference is so small most won’t notice it, however with a dime, it’s so small to begin with that the Canadian ones just stand out. That and there’s a boat on their dimes (or used to be), they just look a lot different at first glance, far moreso than nickels and pennies.

So I guess I always had the expectation that hey, someone handed me this change, no one really noticed the myriad of times this money has changed hands in the past, I don’t feel compelled to separate every last Canadian penny and nickel because I have never had one rejected, except for once, which I will tell you about shortly. Anyway, why should I be the one to take the loss? And most banks don’t even exchange coins, they’ll usually just exchange bills, so it’s like I’ll pull it and keep it if it’s interesting, but generally I try to avoid taking anything larger than nickel (if I notice, and usually it’s not a problem), and with nickels and pennies I’ll just pass them along if I don’t want to keep them. Now for a while the money was at par, that is one US dollar equalled 1 Canadian dollar, but now things are back to where they pretty much have always been, 75 cents US per Canadian dollar, so it can be meaningful if you accept a large volume of change and live close to the border where these things are likely to happen. But still, pennies and nickels you almost never quibble about, dimes and above, you might get an argument, sometimes it’s worth the 8 cent loss or whatever to just keep the damn quarter.

Now there was one time in the early 90s when I think the exchange rate was in the mid 70s where it is now, and I had gone into Canada…I did a pretty good job of keeping my money separate, but apparently one Canadian penny snuck out of my Canadian change into my US change, and I stopped at a convenience store in Indiana…it wasn’t too terribly far from a Canadian border, but far enough that the shopkeeper was unlikely to be seeing Canadian money passed as US currency all that frequently. So, I bought a couple bucks worth of snacks, and I don’t know how much the total was exactly, but let’s say my total ended in a 1 or a 6. I believe I paid in exact change, and they guy isolated from over 2 dollars in mixed currency and change, this one Canadian penny that I didn’t even know was in there and he refused it, said he wanted a different penny. Now most convenience stores even at that time had little penny trays, leave one/take one sort of thing, pennies were already regarded as mostly useless, and essentially this guy legally didn’t have to take my penny, but essentially his “loss” was a quarter of a cent on a purchase of over 2 dollars, a loss which he probably wouldn’t even get stuck with, because he could just pass it along in change. I kind of thought this was really greedy and petty, but he was well within his rights.

So, we get back to our home state, still a hundred miles or so from home and we stop for dinner, this is like a day or two later. We get this waitress who wasn’t just bad, she was willfully negligent and outright rude. Pretty much visited our table twice…once to take our order and once to give us our food. We couldn’t get refills, we couldn’t get napkins, we couldn’t get condiments. But what made matters worse is we saw this waitress many, many times…she’d go to tables next to us, one or two tables away, she went to some of these tables 7 or 8 times, and we couldn’t even wave her down. She would actually walk right by us but put her back to us so she couldn’t see us and then go to someone she’d already waited on. And we had 4 people in our party so it wasn’t like she couldn’t have earned a decent tip.

Well, I believe strongly in tipping, even for marginal to OK service I give 10% because restaurants take 8% out of all checks a server rings up, so tip less than 8%, the server, who already probably doesn’t even make minimum wage, actually LOSES money. But I’d also heard that leaving a penny tip was worse than leaving no tip, because if you left no tip the waitress might think you just forgot, or maybe she won’t even notice your indescretion if it’s on a credit card and you pay at the counter, she might just be told at the end of the night, you $87 in tips from credit cards or whatever. But if you leave a penny, that means you made an effort to tip and intentionally stiffed her. So, I said, “let me leave the tip.”

She got my rejected Canadian penny, and honestly, she didn’t even earn that.

One of my daughters collects foreign currency. Everyone in the family knows to pass it along to her.

put in a jar and let it rot

You know this is pretty common up around Toledo where I grew up, which is only about an hour away from Detroit. I mean as long as its not all canadian coins or something, we always just treated them as the same as regular coins. This is when I worked at McDonalds when I was younger. I think the exchange difference on 10cents or 25 cents is so small it was never really an issue.

I have a little pretty box in my bedroom where I put Canadian coins, Mardi Gras coins, the few Euros I ended up bringing home, and some other teeny tiny odds and ends. I take them out every now and then and have a look.

I save all foreign coins and casino tokens I find in a small container to keep it seperate form my actual money. It’s funny, I have never been to a casino in my life, but I find the damn tokens a lot.

I keep them in my wallet and use them if they are euros from “foreign” countries. Otherwise, there’s a box in our house. The only problem is to remember opening it before the next travel.