Updated

As the amount of counterfeit cash circulating in the country increases, it's worthwhile to take a moment and check your currency to ensure it is legal tender.

The Secret Service offers these pointers:

-- the presidential portrait on the bill should be lifelike and not blend into the background;

-- the jagged border of the Federal Reserve and Treasury seals should be sharp and clear;

-- serial numbers should be evenly spaced and printed in the same ink color as the Treasury Seal.

Authentic currency paper is embedded with tiny red and blue fibers.

For more information on detecting counterfeit money go to:

http://www.secretservice.gov/money_detect.shtml