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Verdigris
Verdigris () is a common name for any of a variety of somewhat toxic copper salt (chemistry), salts of acetic acid, which range in colour from green to a blue-green, bluish-green depending on their chemical composition.H. Kühn, Verdigris and Copper Resinate, in Artists' Pigments. A Handbook of Their History and Characteristics, Vol. 2: A. Roy (Ed.) Oxford University Press 1993, p. 131 – 158 Once used as a medicine and pharmaceutical preparation, verdigris occurs naturally, creating a patina on copper, bronze, and brass, and is the main component of a historic green pigment used for artistic purposes from antiquity until the late 20th century, including in Easel, easel painting, polychromatic sculptures, and illumination of maps. However, due to its instability, its popularity declined as other green pigments became readily available. The instability of its appearance stems from its Hydration number, hydration level and Base (chemistry), basicity, which change as the pigment inte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Pigments
Green pigments are the materials used to create the green colors seen in painting and the other arts. At one time, such pigments came from minerals, particularly those containing compounds of copper. Green pigments reflect the green portions of the spectrum of visible light, and absorb the others. Important green pigments in art history include Malachite and Verdigris, found in tomb paintings in Ancient Egypt, and the Green earth pigments popular in the Middle Ages. More recent greens, such as Cobalt green, Cobalt Green, are largely synthetic, made in laboratories and factories. Today, the main green pigment is Phthalocyanine Green G. Phthalocyanine green image:Phthalocyanine Green G.png, left, Chemical structure of Phthalocyanine Green G, a major green organic pigment, 20px The dominant green pigment is Phthalocyanine Green G, which is sold under many commercial names. It is a synthetic green pigment from the group of phthalocyanines, a complex (chemistry), complex of copper(II) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper(II) Acetate
Copper(II) acetate, also referred to as cupric acetate, is the chemical compound with the formula where is acetate (). The hydrated derivative, , which contains one molecule of water for each copper atom, is available commercially. Anhydrous copper(II) acetate is a dark green crystalline solid, whereas is more bluish-green. Since ancient times, copper acetates of some form have been used as fungicides and green pigments. Today, copper acetates are used as reagents for the synthesis of various inorganic and organic compounds. Copper acetate, like all copper compounds, emits a blue-green glow in a flame. Structure Copper acetate hydrate adopts the paddle wheel structure seen also for related Rh(II) and Cr(II) tetraacetates. One oxygen atom on each acetate is bound to one copper atom at . Completing the coordination sphere are two water ligands, with distances of . The two copper atoms are separated by only , which is close to the separation in metallic copper. The two cop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper(II) Hydroxide
Copper(II) hydroxide is the hydroxide of copper with the chemical formula of Cu(OH)2. It is a pale greenish blue or bluish green solid. Some forms of copper(II) hydroxide are sold as "stabilized" copper(II) hydroxide, although they likely consist of a mixture of copper(II) carbonate and hydroxide. Cupric hydroxide is a strong base, although its low solubility in water makes this hard to observe directly. Occurrence Copper(II) hydroxide has been known since Smelting#Copper and bronze, copper smelting began around 5000 BC although the alchemy, alchemists were probably the first to manufacture it by mixing solutions of lye (sodium or potassium hydroxide) and blue vitriol (copper(II) sulfate). Sources of both compounds were available in antiquity. It was produced on an industrial scale during the 17th and 18th centuries for use in pigments such as blue verditer and Bremen green. These pigments were used in ceramics (art), ceramics and painting. Mineral The mineral of the formula Cu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Composition
A chemical composition specifies the identity, arrangement, and ratio of the chemical elements making up a compound by way of chemical and atomic bonds. Chemical formulas can be used to describe the relative amounts of elements present in a compound. For example, the chemical formula for water is H2O: this means that each molecule of water is constituted by 2 atoms of hydrogen (H) and 1 atom of oxygen (O). The chemical composition of water may be interpreted as a 2:1 ratio of hydrogen atoms to oxygen atoms. Different types of chemical formulas are used to convey composition information, such as an empirical or molecular formula. Nomenclature can be used to express not only the elements present in a compound but their arrangement within the molecules of the compound. In this way, compounds will have unique names which can describe their elemental composition. Composite mixture The chemical composition of a mixture can be defined as the distribution of the individual substance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feces
Feces (also known as faeces American and British English spelling differences#ae and oe, or fæces; : faex) are the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the large intestine. Feces contain a relatively small amount of metabolic waste products such as bacterially-altered bilirubin and dead epithelial cells from the lining of the gut. Feces are discharged through the anus or cloaca during defecation. Feces can be used as fertilizer or soil conditioner in agriculture. They can also be burned as dry animal dung fuel, fuel or dried and used for wattle and daub, construction. Some medicinal uses have been found. In the case of human feces, fecal transplants or fecal bacteriotherapy are in use. Urine and feces together are called excretion, excreta. Characteristics The distinctive odor of feces is due to skatole, and thiols (sulfur-containing compounds), as well as amines and carboxylic acids. Sk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giotto
Giotto di Bondone (; – January 8, 1337), known mononymously as Giotto, was an List of Italian painters, Italian painter and architect from Florence during the Late Middle Ages. He worked during the International Gothic, Gothic and Italian Renaissance painting#Proto-Renaissance painting, Proto-Renaissance period. Giotto's contemporary, the banker and chronicler Giovanni Villani, wrote that Giotto was "the most sovereign master of painting in his time, who drew all his figures and their postures according to nature" and of his publicly recognized "talent and excellence".Bartlett, Kenneth R. (1992). ''The Civilization of the Italian Renaissance''. Toronto: D.C. Heath and Company. (Paperback). p. 37. Giorgio Vasari described Giotto as making a decisive break from the prevalent Byzantine art, Byzantine style and as initiating "the great art of painting as we know it today, introducing the technique of drawing accurately from life, which had been neglected for more than two hundred ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baroque
The Baroque ( , , ) is a Western Style (visual arts), style of Baroque architecture, architecture, Baroque music, music, Baroque dance, dance, Baroque painting, painting, Baroque sculpture, sculpture, poetry, and other arts that flourished from the early 17th century until the 1750s. It followed Renaissance art and Mannerism and preceded the Rococo (in the past often referred to as "late Baroque") and Neoclassicism, Neoclassical styles. It was encouraged by the Catholic Church as a means to counter the simplicity and austerity of Protestant architecture, art, and music, though Lutheran art#Baroque period, Lutheran Baroque art developed in parts of Europe as well. The Baroque style used contrast, movement, exuberant detail, deep color, grandeur, and surprise to achieve a sense of awe. The style began at the start of the 17th century in Rome, then spread rapidly to the rest of Italy, France, Spain, and Portugal, then to Austria, southern Germany, Poland and Russia. By the 1730s, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Renaissance
The Renaissance ( , ) is a Periodization, period of history and a European cultural movement covering the 15th and 16th centuries. It marked the transition from the Middle Ages to modernity and was characterized by an effort to revive and surpass the ideas and achievements of classical antiquity. Associated with great social change in most fields and disciplines, including Renaissance art, art, Renaissance architecture, architecture, politics, Renaissance literature, literature, Renaissance exploration, exploration and Science in the Renaissance, science, the Renaissance was first centered in the Republic of Florence, then spread to the Italian Renaissance, rest of Italy and later throughout Europe. The term ''rinascita'' ("rebirth") first appeared in ''Lives of the Artists'' () by Giorgio Vasari, while the corresponding French word was adopted into English as the term for this period during the 1830s. The Renaissance's intellectual basis was founded in its version of Renaiss ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dicopper Chloride Trihydroxide
Dicopper chloride trihydroxide is the compound with chemical formula . It is often referred to as tribasic copper chloride (TBCC), copper trihydroxyl chloride or copper hydroxychloride. This greenish substance is encountered as the minerals atacamite, paratacamite, and botallackite. Similar materials are assigned to green solids formed upon corrosion of various copper objects. These materials have been used in agriculture. Industrial production Air oxidation of copper(I) chloride in brine solution Large scale industrial production of basic copper chloride was devoted to making either a fungicide for crop protection or an intermediate in the manufacture of other copper compounds. In neither of those applications was the polymorphic nature of the compound, or the size of individual particles of particular importance, so the manufacturing processes were simple precipitation schemes. can be prepared by air oxidation of CuCl in brine solution. The CuCl solution is usually made by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basic Copper Carbonate
Basic copper carbonate is a chemical compound, more properly called copper(II) carbonate hydroxide. It can be classified as a coordination polymer or a salt (chemistry), salt. It consists of copper, copper(II) bonded to carbonate and hydroxide with formula . It is a green solid that occurs in nature as the mineral malachite. It has been used since antiquity as a pigment, and it is still used as such in artist paints, sometimes called verditer, green bice, or mountain green. Sometimes basic copper carbonate refers to ()2()2, a blue crystalline solid also known as the mineral azurite. It too has been used as pigment, sometimes under the name mountain blue or blue verditer. Both malachite and azurite can be found in the verdigris patina that is found on weathered brass, bronze, and copper. The composition of the patina can vary, in a maritime environment depending on the environment a basic chloride may be present, in an urban environment basic sulfates may be present. This compo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brochantite
Brochantite is a sulfate mineral, one of a number of cupric sulfates. Its chemical formula is Cu4SO4(OH)6. Formed in arid climates or in rapidly oxidizing copper sulfide deposits, it was named by Armand Lévy (mineralogist), Armand Lévy for his fellow France, Frenchman, geologist and mineralogist André-Jean-François-Marie Brochant de Villiers, A. J. M. Brochant de Villiers. Crystals of brochantite can range from emerald green to black-green to blue-green, and can be acicular or prismatic. Brochantite is often associated with minerals such as malachite, azurite, and chrysocolla, and may form pseudomorphs with these minerals. The mineral is found in a number of locations around the world, notably the southwestern United States (especially Arizona), Serifos in Greece and Chile. Brochantite is a common corrosion product on bronze sculptures located in urban areas, where atmospheric sulfur dioxide (a common pollutant) is present. Brochantite forms mainly in exposed areas where wea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
