This is known as birefringence, signifying double refraction and produces
interference colors similar to what you see from an oil slick on water--not the colors of the rainbow.
(33.) Dunbar, P, Birnie, III, "Optical Video Interpretation of
Interference Colors from Thin Transparent Films on Silicon." Mater.
Afterward, two component images were subtracted to remove most
interference colors in the yellow area.
Sun has also launched a full range of synthetic micas, including a pearlescent range of silver whites,
interference colors, and metallic golds, bronzes, and russets.
Previous studies have identified cuticular surface and subsurface structures as the cause of
interference colors in spiders.
Suzuki, F, et al., "Adjustment of a High Chroma Pearl Pigment by
Interference Colors of a Laminate which Have a Different Film of a Retractive Index." 80th JSCM Anniversary Conference, 2007
Colorless, transparent, flat/plate-like particles showing second-order and higher
interference colors, characteristic of calcium carbonate, were observed.
An optional module uses proprietary technology for rapid matching of metallic, pearlescent, and
interference colors.