A blend or mixture of inorganic materials used in printing inks to impart a luster characteristic of mother-of-pearl. Pearlescents—commonly co-precipitates of titanium dioxide and mica or other minerals—produce non-metallic shades from silver and gold. They are transparent pigments, with a high refractive index. They are also heat resistant up to 1470ºF. The multiple reflection of light is responsible for their luster, and they are used in screen, lithographic, gravure, and flexographic inks in applications to impart a metal-like sheen when the use of metallic powders is precluded. (See also Pigment.)
('CI Pigment White 6 and 20'.)