Lake pigment
A lake pigment is a pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...

 manufactured by precipitating a dye
A dye is a colored substance that has an affinity to the substrate to which it is being applied. The dye is generally applied in an aqueous solution, and requires a mordant to improve the fastness of the dye on the fiber....

 with an inert
-Chemistry:In chemistry, the term inert is used to describe a substance that is not chemically reactive.The noble gases were previously known as inert gases because of their perceived lack of participation in any chemical reactions...

Binder (material)
-See also:*Adhesive or Glue*Cement*Paint...

, usually a metallic salt. The word lake is a homonym
In linguistics, a homonym is, in the strict sense, one of a group of words that often but not necessarily share the same spelling and the same pronunciation but have different meanings...

 of lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...

 as body of water and does not refer to it.

Manufacturers and suppliers to artists and industry frequently omit the lake designation in the name. Many lake pigments are fugitive
Fugitive pigments
Fugitive pigments are non-permanent pigments that lighten in a relatively short time when exposed to light. Fugitive pigments are present in types of paint, markers, inks etc., which are used for temporary applications...

 because the dyes involved are unstable
Chemical stability
Chemical stability when used in the technical sense in chemistry, means thermodynamic stability of a chemical system.Thermodynamic stability occurs when a system is in its lowest energy state, or chemical equilibrium with its environment. This may be a dynamic equilibrium, where individual atoms...

 when exposed to light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...



The metallic salt or binder used must be inert and insoluble
Solubility is the property of a solid, liquid, or gaseous chemical substance called solute to dissolve in a solid, liquid, or gaseous solvent to form a homogeneous solution of the solute in the solvent. The solubility of a substance fundamentally depends on the used solvent as well as on...

 in the vehicle, and it must be white
White is a color, the perception of which is evoked by light that stimulates all three types of color sensitive cone cells in the human eye in nearly equal amounts and with high brightness compared to the surroundings. A white visual stimulation will be void of hue and grayness.White light can be...

 or very neutral. It must have low tinting strength so that the dye itself determines which wavelengths are absorbed
Absorption (electromagnetic radiation)
In physics, absorption of electromagnetic radiation is the way by which the energy of a photon is taken up by matter, typically the electrons of an atom. Thus, the electromagnetic energy is transformed to other forms of energy for example, to heat. The absorption of light during wave propagation is...

 and reflected
Reflection (physics)
Reflection is the change in direction of a wavefront at an interface between two differentmedia so that the wavefront returns into the medium from which it originated. Common examples include the reflection of light, sound and water waves...

 by the resulting precipitate. In ancient times chalk
Chalk is a soft, white, porous sedimentary rock, a form of limestone composed of the mineral calcite. Calcite is calcium carbonate or CaCO3. It forms under reasonably deep marine conditions from the gradual accumulation of minute calcite plates shed from micro-organisms called coccolithophores....

, white clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...

, and crushed bone
Bones are rigid organs that constitute part of the endoskeleton of vertebrates. They support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...

s were used, being sources of calcium carbonate
Calcium carbonate
Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,...

 and calcium phosphate
Calcium phosphate
Calcium phosphate is the name given to a family of minerals containing calcium ions together with orthophosphates , metaphosphates or pyrophosphates and occasionally hydrogen or hydroxide ions ....

. The salts that are commonly used today include barium sulfate
Barium sulfate
Barium sulfate is the inorganic compound with the chemical formula BaSO4. It is a white crystalline solid that is odorless and insoluble in water. It occurs as the mineral barite, which is the main commercial source of barium and materials prepared from it...

, calcium sulfate
Calcium sulfate
Calcium sulfate is a common laboratory and industrial chemical. In the form of γ-anhydrite , it is used as a desiccant. It is also used as a coagulant in products like tofu. In the natural state, unrefined calcium sulfate is a translucent, crystalline white rock...

, aluminium hydroxide
Aluminium hydroxide
Aluminium hydroxide, Al3, ATH, sometimes erroneously called Hydrate of alumina, is found in nature as the mineral gibbsite and its three, much more rare forms, polymorphs: bayerite, doyleite and nordstrandite. Closely related are aluminium oxide hydroxide, AlO, and aluminium oxide, Al2O3,...

, and aluminium oxide
Aluminium oxide
Aluminium oxide is an amphoteric oxide with the chemical formula 23. It is commonly referred to as alumina, or corundum in its crystalline form, as well as many other names, reflecting its widespread occurrence in nature and industry...

 (alumina), all of which can be produced cheaply from inexpensive mineral ores
Orés is a municipality in the Cinco Villas, in the province of Zaragoza, in the autonomous community of Aragon, Spain. It belongs to the comarca of Cinco Villas. It is placed 104 km to the northwest of the provincial capital city, Zaragoza. Its coordinates are: 42° 17' N, 1° 00' W, and is...


History and types

Lake pigments have a long history in decoration and the arts. Some have been produced for thousands of years and traded over long distances.
  • Indigo lake
    Indigo dye
    Indigo dye is an organic compound with a distinctive blue color . Historically, indigo was a natural dye extracted from plants, and this process was important economically because blue dyes were once rare. Nearly all indigo dye produced today — several thousand tons each year — is synthetic...

     was originally produced from the leaves of woad
    Isatis tinctoria, with Woad as the common name, is a flowering plant in the family Brassicaceae. It is commonly called dyer's woad, and sometimes incorrectly listed as Isatis indigotica . It is occasionally known as Asp of Jerusalem...

    , and was known in ancient Egypt
    Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...

    . In the late Middle Ages
    Late Middle Ages
    The Late Middle Ages was the period of European history generally comprising the 14th to the 16th century . The Late Middle Ages followed the High Middle Ages and preceded the onset of the early modern era ....

    , a fashion for woad as a textile dye led to overplanting and soil exhaustion in many parts of Europe
    Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

    . After trade routes opened to the east, indigo
    Indigofera tinctoria
    Indigofera tinctoria bears the common name True indigo. The plant was one of the original sources of indigo dye. It has been naturalized to tropical and temperate Asia, as well as parts of Africa, but its native habitat is unknown since it has been in cultivation worldwide for many centuries. Today...

     was imported from India
    India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

     as a substitute for woad, and the cultivation of woad became uneconomical in Europe. Today, the dark blue dye known as indigo once produced from woad and Indigofera tinctoria is largely of synthetic origin. The dye and pigment are both fugitive.

  • Rose madder lake
    Rose madder
    Rose Madder is the commercial name sometimes used to designate a paint made from the pigment Madder Lake - a traditional lake pigment, extracted from the common madder plant ....

    , originally from the root of the madder
    Rubia is a genus of the madder family Rubiaceae, which contains about 60 species of perennial scrambling or climbing herbs and sub-shrubs native to the Old World, Africa, temperate Asia and America...

     plant, is also known as alizarin crimson in its synthetic form. Since rose madder is fugitive when exposed to light, its use has been largely superseded, even in synthetic form, by quinacridone
    Quinacridone is a red powder. It is an organic compound with the molecular formula C20H12N2O2. It is used as a pigment; analogs bearing this motif are known as quinacridones.-Quinacridones:...


  • Carmine lake
    Carmine , also called Crimson Lake, Cochineal, Natural Red #4, C.I. 75470, or E120, is a pigment of a bright-red color obtained from the aluminum salt of carminic acid, which is produced by some scale insects, such as the cochineal beetle and the Polish cochineal, and is used as a general term for...

     was originally produced from the cochineal insect
    The cochineal is a scale insect in the suborder Sternorrhyncha, from which the crimson-colour dye carmine is derived. A primarily sessile parasite native to tropical and subtropical South America and Mexico, this insect lives on cacti from the genus Opuntia, feeding on plant moisture and...

    , native to Central
    Central America
    Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...

     and South America
    South America
    South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

    . It is also called crimson lake. When the Spanish conquered
    Spanish colonization of the Americas
    Colonial expansion under the Spanish Empire was initiated by the Spanish conquistadores and developed by the Monarchy of Spain through its administrators and missionaries. The motivations for colonial expansion were trade and the spread of the Christian faith through indigenous conversions...

     the Aztec Empire (1518-1521), they encountered Aztec warriors garbed in an unknown crimson color. Cochineal became their second most valuable export
    The term export is derived from the conceptual meaning as to ship the goods and services out of the port of a country. The seller of such goods and services is referred to as an "exporter" who is based in the country of export whereas the overseas based buyer is referred to as an "importer"...

     from the New World, after silver
    Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...

    , and the Spanish zealously guarded the secret of its production for centuries. Carminic acid
    Carminic acid
    Carminic acid is a red glucosidal hydroxyanthrapurin that occurs naturally in some scale insects, such as the cochineal and the Polish cochineal. The insects produce the acid as a deterrent to predators. Carminic acid is the colouring agent in carmine. Synonyms are C.I. 75470 and C.I...

    , the organic compound
    Organic compound
    An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon, and cyanides, as well as the...

     which gives carmine its color, was synthesized
    Organic synthesis
    Organic synthesis is a special branch of chemical synthesis and is concerned with the construction of organic compounds via organic reactions. Organic molecules can often contain a higher level of complexity compared to purely inorganic compounds, so the synthesis of organic compounds has...

     in 1991.

Indigo and rose madder are now produced more cheaply from synthetic sources, although some use of natural products persists, especially among artisans. The food
Food industry
The food production is a complex, global collective of diverse businesses that together supply much of the food energy consumed by the world population...

 and cosmetics industries
Cosmetics are substances used to enhance the appearance or odor of the human body. Cosmetics include skin-care creams, lotions, powders, perfumes, lipsticks, fingernail and toe nail polish, eye and facial makeup, towelettes, permanent waves, colored contact lenses, hair colors, hair sprays and...

have shown renewed interest in cochineal as a source of natural red dye.
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