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Pigment
In biology, pigment is any material resulting in color in plant
or animal cells which is the result of selective absorption. Some
biological material has so-called structural color, which is the
result of selective reflection or iridescence, usually done with
multilayer structures. Unlike structural color, pigment color is
the same for all viewing angles. Nearly all types of cells, such
as skin, eyes, fur and hair contain pigment. Butterfly wings typically
contain structural color, although many of them contain pigment
as well. Creatures that have deficient pigmentation are called albinos.
Because pigment color is the result of selective absorption, there
is no such thing as white pigment. A white object is simply a diffuse
reflecting object which does not contain any pigment.
In the coloring of paint, ink, plastic, fabric and other material,
a pigment is a dry colorant, usually an insoluble powder. There
are both natural and synthetic pigments, both organic and inorganic
ones. Pigments work by selectively absorbing some parts of the visible
spectrum (see light) whilst reflecting others.
A distinction is usually made between a pigment, which is insoluble,
and a dye, which is either a liquid, or is soluble. There is a well-defined
dividing line between pigments and dyes: a pigment is not soluble
in the vehicle while a dye is. From this follows that a certain
colourant can be both a pigment and a dye depending on in which
vehicle it is used. In some cases, a pigment will be made by precipitating
a soluble dye with a metallic salt. The resulting pigment is called
a "lake".
List of pigments
Heme/Porphyrin based
Chlorophyll
Bilirubin
Hemocyanin
Hemoglobin
Myoglobin
Light emitting
Luciferin
Lipochromes
Carotenoids
Alpha and Beta Carotene
Cyanins
Anthocyanin
Lycopene
Rhodopsin
Xanthophylls
Canthaxanthin
Zeaxanthin
Lutein
Photosynthetic
Chlorophyll
Phycobilin
Other
Hematochrome
Melanin - Which causes human skin coloration
Phthalocyanine blue
Urochrome
polyene enolates are a class of red pigments unique to parrots.
Painting pigments
Alizarin (Alizarin Crimson)
Bone black (also known as bone char)
Cadmium pigments (Cadmium Green, Cadmium Red, Cadmium Yellow, Cadmium
Orange)
Caput Mortuum
Carbon black
Cerulean blue
Chromium pigments (Chrome Green, Chrome Yellow)
Cobalt pigments (Cobalt Blue)
Crimson
Fugitive pigments
Gamboge
Indian Yellow
Indigo
Ivory black
Vine black
Lamp black
Mars black
Lead pigments (Lead white, Naples Yellow, Cremnitz White, Foundation
White, Red Lead)
Paris Green
Phthalocyanine (Phthalo Green, Phthalo Blue)
Prussian blue
Quinacridone (Quinacridone Magenta)
Oxide Red
Red ochre
Sanguine
Sienna (Raw Sienna, Burnt Sienna)
Titanium dioxide (Titanium White)
Ultramarine (Ultramarine Green Shade, French Ultramarine)
Umber (Raw Umber, Burnt Umber)
Van Dyke brown
Venetian Red
Verdigris
Vermillion
Viridian
Yellow ochre
Zinc white
The paintings are the excellent portrayal of the events and scenes
that we see around us. The painters are the best cameras of the
world. They reproduce many different types of pictures. They even
draw imaginary pictures that do not exist in this world. We tend
to use both thinned oil paints and dense oil paints. Masterpieces
can be dyed more than once, but each time it may be different from
the existing paintings.
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