Hmm, guess that would make the import duty a moot point as we'd still be part of Britain then, lol... I've never actually had to pay import duty on anything as I've never taken anything of significant value across international borders. Not sure how it works the other way around for some countries, but I know that bringing stuff INTO the US, you don't have to pay any duty on it unless the value exceeds $400 US (not counting some alcohol and tobacco products that have duties past a certai physical amount). I've sent stuff to eBay winners internationally before, always declared them as gifts worth whatever the winning bid was on them. Not sure if the winners had to pay any duty on them or not; I know as the sender I didn't have to.
A few years ago I was asking Scotiabank some questions about Canadian bullion coins and they told me that the reason for putting a dollar denomination on coins was to permit them to cross international borders duty-free. I guess it doesn't work everywhere.
Depends on the laws of the country you're taking it into, but some countries have a loophole that does not require you to pay any duty on currency... which is why you can get away with transporting coins without duty sometimes if they're technically legal tender, even if their numismatic or intrinsic value exceeds their nominal face value. However let me re-emphasize it depends entirely on the laws of the country you're bringing it into; check first!
