How Benjamin Franklin fought money counterfeiters

Blue threads and muscovite, a reflective mineral, were incorporated into paper bills

An illustration of young Benjamin Franklin at the printing press.

Benjamin Franklin and his associates printed paper money for the mid-Atlantic region in the early colonial United States. His bills included blue thread and muscovite, possibly as a counterfeit tactic.

Library of Congress

Though perhaps better known for its newspapers and almanacs, Benjamin Franklin’s printing business also churned out paper money to support the colonial economy.