![]() ![]() ![]() Plant pigments exist in a wide variety of forms, some with highly complex and large structures. All biological pigments selectively absorb certain wavelengths of light while reflecting others.Ĭolor arises from the way the pigments react with light. They can be found in many plants, including flowers, and even in our skin. Biological pigmentsīiological pigments are pigments produced by living organisms. Pigments color paint, ink, plastic, fabrics, cosmetics, food, and a wide range of products we use and see all about us. Lead compounds used to find widespread applications in white and gray paints, but are now rarely used because of their toxicity. ![]() Cadmium sulphide owes its distinctive color to the mechanism described by band gap theory. The mechanism described by ligand theory causes the color of the pigment chrome green. Ultramarine or lazurite (found in the gemstone lapis lazuli) is colored by the charge transfer process. Some pigments have been categorized on this site in terms of the mechanism that causes a particular wavelength or group of wavelengths to be reflected rather than absorbed. Vermilion is a mercury compound and has been replaced by convenient mixtures of synthetic, inorganic pigments. Historically, artists such as Titian used the pigment Vermilion to create the reds in the great fresco of Assunta, completed c. Many early artists used natural pigments, but nowadays they have been replaced by cheaper and less toxic synthetic pigments. The WebExhibit on Pigments has more information on these early painting palettes. These colors occurred naturally in charcoals, and in mineral oxides such as chalk and ochre. This makes them appear "colorful.”Ĭave paintings by early man show the early use of pigments, in a limited range from straw color to reddish brown and black. Pigments absorb some of the light they receive, and so reflect only certain wavelengths of visible light. Pigments are chemical compounds responsible for color in a range of living substances and in the inorganic world. Colors signal harvest time, breeding conditions, and the change of seasons, from the first greens of spring to the brilliant reds and browns of the fall. Color plays a multitude of roles in the natural world, used to entice, to camouflage, or to warn other creatures. The plant and animal kingdoms abound with bright colors, from the lush green of photosynthesizing plants to the bold black and orange stripes of tigers. A tiger’s stripes allow him to disappear into the jungle shadows. ![]()
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