I just saw a casheir at walmart check a 20 for the ghost yesterday. They don't rely on pens anymore.. or how real they look.. but there are a lot of fake 20's floating around here.. But how the pens work are.. the pens are iodine. When the iodine mixes with starch.. which is found in printing paper.. it will give that dark brown color. Thats why rag paper passes.. or anything that has no starch in it.. Like a coffee filter.. But if you do use printer paper.. the feel isn't there. But a light coat of hairspray passes the paper for "real" with the pen test. |