How Benjamin Franklin Helped Foil Early American Money Counterfeiters

Scientists identified specific pigments, minerals and fibers used in the bills 

By Jo Craven McGinty of The WSJ. Excerpts:

"Franklin, who was a printer, among his other roles, was known for marking his early paper money with images of intricately veined leaves that were nearly impossible for counterfeiters to copy, using a variety of fonts, some available only to him, and intentionally lacing the text with misspellings.

But scientists say Franklin took things a step further to stave off fraudsters. Other distinguishing characteristics of Franklin’s money—the new research revealed through advanced atomic-level imaging methods—were more subtle. He used a unique black ink. His paper glimmered. Blue threads decorated the surface, and finer fibers were woven throughout."

"Franklin and his associates held lucrative government contracts to print the paper currencies of the Pennsylvania, New Jersey and Delaware colonies. Later, after Franklin retired, his associates carried on with the novel techniques leading up to the Revolutionary War, when the Continental Congress ordered the first national currency to finance the American Revolution. Their bills bore their names—“B. Franklin” or “Hall and Sellers,” for example, identifying Franklin, his former business partner David Hall, and Hall’s subsequent partner, William Sellers."

"Researchers discovered that the black ink used by Franklin and his associates was made of graphite. The blue threads in their bills were dyed with indigo, a plant-based pigment. Their paper was strengthened with muscovite, a variety of mica."

"“He has small muscovite inside the paper early on,” Manukyan said. “Then we see it appear on the surface and glimmer. No others had this among those we analyzed. Indigo-colored threads were unique to Benjamin Franklin’s money. The black pigment is a more vivid black than the others.”"

"While it is difficult to know to what extent counterfeiting occurred, it is evident that it was a concern. 

Some bills bore the warning “To counterfeit is Death,” a reminder that making funny money was a capital offense. And Franklin, John Adams and others expressed concern that the British government was circulating fake bills to undermine the colonial economy and rebellion. 

Amid those concerns, the Continental Congress recalled more than 41 million Continental dollars, swapping new bills for two lots of compromised notes."

"Today, modern currency incorporates safeguards that are reminiscent of the techniques Franklin pioneered.

The hundred-dollar bill, which bears Franklin’s portrait, is protected by a 3-D blue security ribbon that is woven into the note. A pink security thread is concealed in the fiber. Color-shifting numerals change from copper to green. A hologram of the Liberty Bell and a faint watermark tattoo the paper."