I noticed that the Italian jeton maker Abiatti - http://www.abbiati.com/Index_Intro.htm - has released some new "security" chips. The website includes a demo that seems to illustrate the chip inserts (and to some extent the inlay) shifting colors. I was wondering how this effect is accomplished? Are the chips luminescent (that would be cool!)? Or is the insert made with a special material that changes color when viewed from different angles?