Some or all of this article's listed sourcesmay not be reliable. Please help this article by looking for better, more reliable sources, or by checking whether the references meet the criteria for reliable sources. Unreliable citations may be challenged or deleted.(September 2012)
Pearlescent or nacreouscoatings or pigments possess optical effects that not only serve decorative purposes (such as cosmetics, printed products, industrial coatings, or automotive paints), but also provide important functional roles, such as security printing or optical filters.