
When Should You Use Iridescent, Pearl, and Interference Colors? There is a place for iridescent, pearl, and interference colors in both fine arts and crafts. These conventional pigments are oftentimes combined with powdered aluminum silicate (powdered mica) or powdered bronze in order to yield a complex effect – such as a reflecting characteristic or a shimmering characteristic. The effect achieved will depend on the fineness or coarseness of the mica or powdered bronze that is used.