(Sarah of the Clue Crew reads from a printing press at the Bureau of Engraving and Printing in Washington, D.C.)  The color of the first ink used in printing $1 bills & the part of the sheet it goes on gives us this word that dates from 1862
Up-to-date information about the SPMC, including its 
bylaws and .... Color $50 Jefferson Blue $100 Jackson Blue $500 Washington ... 
259 5 First Liberty Loan Bond 4% Converted Issued November 15, 1917.