Example of mint cancellation?

[brandm24]

I came across this 1967 6p that's oddly defaced. Would this be something done at the mint ro "cancel" the coin or is it a private defacement? Any thoughts?

Bruce

[Figleaf]

It looks like someone placed a coin between two cog wheels and the wheels ate right through them. If so, the incuse portions on one side should be opposite untouched areas on the other side.

The method would remind me of the origin of the word "sabotage".

Peter

[FosseWay]

I think that comes into the category of "unauthorized aftermarket modification" 

IME cancellations do either or both of the following: (a) obliterate as much of the coin's design as possible to make it not obvious at first glance what its former face value was, and/or (b) stamp a word (CANCELLED or similar) that explicitly says what's happened to it. I have a Romanian coin countermarked with the word ANULAT (cancelled in Romanian) across the entire planchet, for example.

The damage to that sixpence does not automatically render it unusable. I've received bent or otherwise damaged coins in change before, and have passed them on without a problem. It's in the authorities' interests to make any cancellation notably different from the kind of damage that a coin will still be generally accepted with.

Finally, in the specific case of the sixpence I don't see any particular reason why the coins should have been cancelled at all. They were legal tender up to a given point, so no need to cancel them, and then they weren't, and were therefore useless as coins (though retained their metal value, of course). I'm not sure what the Royal Mint would have had to gain by cancelling them, but I may have misunderstood something.

[brandm24]

The "unauthorized aftermarket modifications" didn't look extensive enough to render the coin useless to me either. I know when the US Mint defaces coins, dies or spoiled planchets they really go at it. Not much left to identify when they're done. I wasn't sure how other mints handle these things.

Well, FosseWay, you've given a new more elegant name to the things I collect, counterstamps. I've always thought of it as controlled destruction, but somehow UAM seems so much more refined.

Bruce

[FosseWay]

Haha

My day job involves preparing (authorized) aftermarket materials for cars - user manuals, diagnostics, the error messages that flash up in front of you when something goes wrong, that kind of thing. Most of the control units in modern cars can set trouble codes along the lines of "this doesn't work because the user has installed a non-standard part". This kind of thing generally gets called things like "unauthorized aftermarket modification".