Analysis of information sources in references of the Wikipedia article "Security printing" in English language version.
Prismatic Two-Colour Pantograph A multi-colour background in which two colours change density and blend into each other, making it very difficult to reproduce
{{cite journal}}: Cite journal requires |journal= (help)banknote designers succumb to the Titanic effect
Pearlescent Pigments are made from mica and they are widely used in paints, coating, printing ink, plastic, cosmetic, leather, wallpaper etc.[dead link]