From dsinclai at acs.ucalgary.ca Fri Jul 30 17:30:03 1993 From: dsinclai at acs.ucalgary.ca (Douglas Sinclair) Date: Fri, 30 Jul 93 17:30:03 PDT Subject: Bank notes Message-ID: <9307310029.AA49095@acs1.acs.ucalgary.ca> Canada now uses holograms on its $20, $50, $100 and $1000 bills. They're a small patch on the top right hand corner that looks like gold foil. Written on this foil is the denomination of the bill (20, 50, &c). As the viewing angle is changed, the color of this writing shifts. Obviously, this will blow a photocopier out of the water. I have minimal experience in holography, but it would also seem to be difficult to print one on a metal foil. -- PGP 2.3 Key by finger