Certain crimes have seasons and Cleburne police warn, "counterfeit currency season is in full bloom."
The police department said counterfeit bills have been passed at local retailers and restaurants, but that the concern this year is a spike in "washed" notes.
WHAT IS A 'WASHED' NOTE?
"A 'washed' note is an authentic U.S. currency note that has been washed of its original markings and then reprinted with markings of a higher denomination," the department said in a news release. "For example, a criminal will 'wash' a $5 note and reprint it as a $100 note."
Get top local stories in DFW delivered to you every morning. >Sign up for NBC DFW's News Headlines newsletter.
Police said the problem with this type of counterfeit is the bill will pass the "pen test," where a special marker is used to check the paper to make sure that it's a real bill because the paper itself is real.
Police say a counterfeit pen test shouldn't be the only tool used to detect a fake bill, a black light can also be used but also isn't definitive.
HOW TO KNOW A BILL IS REAL: PAY ATTENTION TO DETAIL
Local
The latest news from around North Texas.
Police said it's important to pay attention to detail.
"Counterfeit notes, because of the nature of reprinting the note, are notoriously sloppy. Look for smudged printing, lack of detail, or faded printing," the news release said.
Another important detail to check is the specialized ink.
Newer U.S. currency designs found on newer $10, $20, $50, and $100 bills, the ones with the larger presidential portraits, have metallic-looking color-shifting ink-printed denominations on the face in the lower right corner. Police said the metallic-colored ink should change colors as you tilt it back and forth if it is a real bill.
Police said you should also check the ink quality.
When reprinting counterfeit bills, criminals often use standard ink like in a home office inkjet printer which is lower quality. Police said if a bill is real and you rub the corner between your fingers, the ink will hold and not smear or smudge. With counterfeit currency, the ink will smear and smudge, or you'll see the quality of the print visibly diminish.
Also, hold the bill up to the light and check that the security thread inside the bill matches the denomination on the bill. On a $100, the security thread denotes 100.
The watermark on bills $10 and higher will also match the large portrait. The $5 note has two watermarks, both of the numeral 5.
WHAT TO DO IF YOU SUSPECT COUNTERFEIT CURRENCY
U.S. Secret Service's website advises if you suspect counterfeit currency contact your local police department. Your local bank may also assist in identifying counterfeit currency.