I follow a guy on Twitter who posts pictures from medieval manuscripts, and today he posted pics from a page from 1482 that had warnings about fake Netherlandish coins. I've attached
the pictures, which are from a manuscript at the Bodleian (Bodleian oulis2009-btj0049). The pictures are what the coins are supposed to look like.
I don't know anything about Netherlandish coins, but thought it might be of interest to those that do.
Thanks! - here's the complete page image. Counterfeiting is nothing new and it's interesting to see this early instance of a counterfeit detection piece in print.