What color does money turn if its fake?

What color does money turn if its fake?

When the pen is used to mark genuine bills, the mark is yellowish or colourless.

How can you tell if a $100 bill is counterfeit?

To check if a 100 dollar bill is real, start by holding the bill up the light to view the embedded thread next to Franklin which reads “USA” and “100.” Next, look to see if the ink to the left of the serial number changes from copper to green when you move the bill around.