MAKING MONEY
'(<a href="http://www.j-archive.com/media/2008-10-09_DJ_12.wmv">Sarah of the Clue Crew reads from a printing press at the Bureau of Engraving and Printing in Washington, D.C.</a>)  The color of the first ink used in printing $1 bills & the part of the <a href="http://www.j-archive.com/media/2008-10-09_DJ_12.jpg" target="_blank">sheet</a> it goes on gives us this word that dates from 1862'
greenback