Biological pigment symbiosis Trididemnum solidum, their colors are different depending on the light regime in which they live. The colonies that are exposed to full sunlight are heavily calcified, thicker, and are white. In contrast the colonies that live in shaded areas have more phycoerythrin (pigment that absorbs green) in comparison to phycocyanin (pigment that absorbs red), thinner, and are purple. The purple color in the shaded colonies are mainly due to the phycobilin pigment of the algae, meaning the variation of exposure in light changes the colors of these colonies. Aposematism is the warning coloration to signal potential predators to stay
Alumina effect pigment of all layers in the pigment structure, including the AlOsubstrate. Analytical investigations show that the thickness range of the aluminum oxide platelets and the resultant pigments can be controlled very precisely. The sparkle effect of the pigments in coating applications is controlled by the quantity of the added pigment. The effect is visible already at concentrations of 0.1% in the paint system. The intensity is steadily increased up to pigment concentrations of about 2%. The single light spots arising from the pigment structure and orientation in the paint system seem to spring back and forth when a painted metal plate