Below is a copy and paste of an article on the subject. 'Twas some years back. I cannot find any other stuff online... but I'm well aware of the situation.

In an article(which I will continue to look for), some knowledgable individual determined they were remarkable copies...
in everyway, other than a smooth edge(a little smaller dia) and heavy pitting... and it was determined it would cost more to produce the counterfeit than the quarter is worth.
As it turns out these quarters lived most of their life at the Winnipeg casino(hey,there's a mint in Winnipeg!). Further tests showed they were not counterfeit, but well worn with the reeding worn off. The casino has since gone to an e-card system, as most have. I can't find an article on the embarassed, eventual truth(go figure).

But yes, because of the commotion, I did saved a few.
VVV Article VVV
COUNTERFEIT QUARTERS
Back in April the Toronto Sun ran an article entitled "Two-bit scam pops up in North". This covered the
story of counterfeit quarters being released in Thunder Bay. Apparently these quarters "can be easily
detected by their pitted surfaces and the lack of serrated edges".
CAMA asked The Mint whether these coins are accepted by electronic acceptors? And, if so, as old
coins or plated. They undertook to investigate, and here is their answer.
"The counterfeit coins would be accepted by the electronic acceptors as old coins, i.e. nickel coins".
VVV Space For Embarassed Truth Article VVV
