Counterfeit Coins - How Prevalent

In general, counterfeits and alterations only make up a small percentage of all coins though some coins are more prone to counterfeits and alterations than others. Unfortunately that percentage has been increasing lately and depending on where and from whom you are purchasing from, your odds of purchasing a fake can be much higher. To give you an idea, PCGS publishes statistics showing the number of coins they have graded, crossovers, number of problem coins, and number of warranty claims. According to them, out of the nearly 2 million they have graded in the last 12 months, 5541 were returned as questionable authenticity. In the last 30 days, around 123,000 were graded and 526 were returned as questionable authenticity. That gives percentages of 0.28% and 0.43% respectively. The percentages when it comes to raw coins would probably be a bit higher since I would think some of the coins would have been screened before submitting. For those who would like to see those statistics, the link is below.
http://www.pcgs.com/statistics/

I am not completely sure but I think it is if they graded the coin at least what you stated as the minimum grade.

You can't cross 70's. You have to give them permission to crack them out and treat them as a raw submission.

The real problem with that is no one really knows how many or what has been counterfeited. For every one known, there could well be hundreds or even thousands in collections and in dealers inventories. Most people do not send in every coin they find or buy to a TPGS. And many times I wonder if those can really tell all fakes since a TPGS is just people hired to do a job. But if other countries, China is not the only one, are producing faked US coins, there could be many, many in collections without anyone knowing for sure.
I used to know a dealer that was in the buisness for a real long time. He had a 16D Mercury dime he thought was real. Finally he sent it out for grading and it came back a fake. He sent to another TPGS and it came back graded and slabbed.
So many fakes are popping up every day I wonder why we just don't have China make all our coins now.