band_on_the_run, 1 year ago

You’re thinking of older US paper currency, which was shades of green for a lot of its history. Over the years they’ve modified it to include other colors and introduced numerous security features, all in an effort to make it very difficult to counterfeit.

Here are a couple of examples of how bills looked when I was young:

numismaclub.com/…/10_1981_cu_trio_chicago_il_frn_…

usrarecurrency.com/…/1996$50FRNSnAA20022001A.jpg