There’s no shortage of cash circulating around the economy – about $824 billion, according to a University of Wisconsin study.

But a good chunk of that cash – $64 million based on one estimate – may not be on the up and up.

Counterfeit currency is a problem that just won’t go away, despite the increased use of credit and debit cards, and e-payment technologies. Whether it’s a street hustler passing off bogus $10 bills or professional counterfeiters dealing in heavy doses of $50 and $100 bills, fake currency has the full attention of the U.S. Treasury, Federal Bureau of Investigation (FBI) and the United States Secret Service.

But, as the Secret Service points out, the American public has a significant role to play in uncovering counterfeit currency. Small business owners and retail cashiers should be trained to examine and identify phony bills – but the truth is that anyone can learn to spot a piece of counterfeit cash.

Here are some tips on how to get a handle on bogus bills – they’re relatively easy to learn and can turn you into a sharp-eyed connoisseur of counterfeit cash.

Light it up – The Secret Service advises taking a questionable bill and holding it up under bright lighting. If it’s a good bill, you’ll see a holograph on the face-up side of the bill. Ideally, both of the images should match up perfectly. Under the same light, you should notice a thin vertical strip with text that spells out the currency’s denomination.

Look for changes in color – The U.S. Treasury offers this tip. Take any bill other than the $5 note and move it back and forth (ideally tilting it as you do so). You should notice a number in the lower right hand corner. If the bill’s good, the number’s color will shift from green to black and back again.

Go ultraviolet – An easy way to tell if a bill is authentic or not is to hold it up to ultraviolet light. Here’s what to look for:

•    $5 bills glow blue
•    $10 bills glow orange
•    $20 bills glow green
•    $50 bills glow yellow
•    $100 bills glow red

If the bill doesn’t appear as described above, then you’ve got a bogus bill on your hands.

Play the numbers – An authentic bill has serial numbers that are cleanly spaced and are always printed in the same color ink as the Treasury Seal. With a fake piece of currency, the numbers may not seem so evenly spaced, and the numbers may have a different color than the Treasury Seal.

The U.S. Treasury has some direct advice if you encounter a phony bill.

1.    Keep the bill in your possession, but get a good description of who or where you got it from.
2.    Write down the license number of the passer of the bill, if possible.
3.    Contact either the police department or the Secret Service.
4.    Place the counterfeit bill in a safe packet or envelope.
5.    Do not actively accuse or engage the bill-passer. Leave that to the authorities.

If you own your own business, or handle cash as part of your job, it’s a smart move to buy an ultraviolet light or counterfeit detection devices. Most business supply stores carry them or you can buy them online.

Handling counterfeit cash isn’t a game. If you suspect a bad bill is on your possession, take account of the person who gave it to you and call the authorities. Then get out of the way and let the law enforcement professionals handle the rest.

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