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Indian Red (color)
Iron oxide red is a generic name of a ferric oxide pigment of reddish colors. Multiple shades based on both anhydrous and its hydrates were known to painters since prehistory. The pigments were originally obtained from natural sources, since the 20th century they are mostly synthetic. These substances form one of the most commercially important groups of pigments, and their names sometimes reflect the location of a natural source, later transferred to the synthetic analog. Well-known examples include the Persian Gulf Oxide with 75% and 25% silica, Spanish red with 85% of oxide, Tuscan red. Other shades of iron oxides include Venetian Red, English Red, and Kobe. Properties The anhydrous pigment has a dark purple-red or maroon color, hydrates' colors vary from dull yellow ( yellow ochre) to warm red. The iron oxide red is extremely stable: it is not affected by light and most chemicals (soluble in hot concentrated acids); heat only affects the hydrated variants (the wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Oxide Pigments
Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's outer and inner core. It is the fourth most abundant element in the Earth's crust, being mainly deposited by meteorites in its metallic state. Extracting usable metal from iron ores requires kilns or furnaces capable of reaching , about 500 °C (900 °F) higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BC and the use of iron tools and weapons began to displace copper alloys – in some regions, only around 1200 BC. That event is considered the transition from the Bronze Age to the Iron Age. In the modern world, iron alloys, such as steel, stainless steel, cast iron and special steels, are by far the most common industrial metals, due to their mechanical pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pigment
A pigment is a powder used to add or alter color or change visual appearance. Pigments are completely or nearly solubility, insoluble and reactivity (chemistry), chemically unreactive in water or another medium; in contrast, dyes are colored substances which are soluble or go into solution at some stage in their use. Dyes are often organic compounds whereas pigments are often inorganic compound, inorganic. Pigments of prehistoric and historic value include ochre, charcoal, and lapis lazuli. Economic impact In 2006, around 7.4 million tons of inorganic chemistry, inorganic, organic chemistry, organic, and special pigments were marketed worldwide. According to an April 2018 report by ''Bloomberg Businessweek'', the estimated value of the pigment industry globally is $30 billion. The value of titanium dioxide – used to enhance the white brightness of many products – was placed at $13.2 billion per year, while the color Ferrari red is valued at $300 million each yea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Talyllyn Railway
The Talyllyn Railway () is a narrow-gauge railway in Wales running for from Tywyn on the Mid-Wales coast to Nant Gwernol railway station, Nant Gwernol near the village of Abergynolwyn. The line was opened in 1865Drummond 2015, page 17 to carry slate from the quarries at Bryn Eglwys to Tywyn, and was the first narrow gauge railway in Britain authorised by Act of parliament#United Kingdom, Act of Parliament to carry passengers using steam haulage. Despite severe underinvestment, the line remained open, and in 1951 it became the first railway in the world to be preserved as a heritage railway by volunteers. Since preservation, the railway has operated as a tourist attraction, expanding its rolling stock through acquisition and an engineering programme to build new locomotives and carriages. In 1976, an extension was opened along the former mineral line from Abergynolwyn to the new station at Nant Gwernol. In 2005 a major rebuilding and extension of Tywyn Wharf railway station, Ty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indigenous Peoples Of The Americas
In the Americas, Indigenous peoples comprise the two continents' pre-Columbian inhabitants, as well as the ethnic groups that identify with them in the 15th century, as well as the ethnic groups that identify with the pre-Columbian population of the Americas as such. These populations exhibit significant diversity; some Indigenous peoples were historically hunter-gatherers, while others practiced agriculture and aquaculture. Various Indigenous societies developed complex social structures, including pre-contact monumental architecture, organized city, cities, city-states, chiefdoms, state (polity), states, monarchy, kingdoms, republics, confederation, confederacies, and empires. These societies possessed varying levels of knowledge in fields such as Pre-Columbian engineering in the Americas, engineering, Pre-Columbian architecture, architecture, mathematics, astronomy, History of writing, writing, physics, medicine, Pre-Columbian agriculture, agriculture, irrigation, geology, minin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Color Metaphors For Race
Identifying race (human categorization), human races in terms of Human skin colour, skin colour, at least as one among several physiological characteristics, has been common since antiquity. Such divisions appeared in early modern scholarship, usually dividing humankind into four or five categories, with colour-based labels: red, yellow, black, white, and sometimes brown. It was long recognized that the number of categories is arbitrary and subjective, and different ethnic groups were placed in different categories at different points in time. François Bernier (1684) doubted the validity of using skin color as a racial characteristic, and Charles Darwin (1871) emphasized the gradual differences between categories. There is broad agreement among modern scientists that typological conceptions of race have no scientific basis. History Antiquity to 1600s Categorization of racial groups by reference to skin color is common in classical antiquity. For example, it is found in e.g. ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Etymology
Etymology ( ) is the study of the origin and evolution of words—including their constituent units of sound and meaning—across time. In the 21st century a subfield within linguistics, etymology has become a more rigorously scientific study. Most directly tied to historical linguistics, philology, and semiotics, it additionally draws upon comparative semantics, morphology, pragmatics, and phonetics in order to attempt a comprehensive and chronological catalogue of all meanings and changes that a word (and its related parts) carries throughout its history. The origin of any particular word is also known as its ''etymology''. For languages with a long written history, etymologists make use of texts, particularly texts about the language itself, to gather knowledge about how words were used during earlier periods, how they developed in meaning and form, or when and how they entered the language. Etymologists also apply the methods of comparative linguistics to reconstruct in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crayon
A crayon (or wax pastel) is a stick of pigmented wax used for writing or drawing. Wax crayons differ from pastels, in which the pigment is mixed with a dry binder (material), binder such as gum arabic, and from oil pastels, where the binder is a mixture of wax and oil. Crayons are available in a range of prices, and are easy to work with. They are less messy than most paints and markers, blunt (removing the risk of sharp points present when using a pencil or pen), typically non-toxic, and available in a wide variety of colors. These characteristics make them particularly good instruments for teaching small children to draw in addition to being used widely by student and professional artists. Composition In the modern English-speaking world, the term crayon is commonly associated with the standard wax crayon, such as those widely available for use by children. Such crayons are usually approximately in length and made mostly of paraffin wax. Paraffin wax is heated and cooled to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crayola
Crayola LLC, formerly the Binney & Smith Company, is an American manufacturing and retail company specializing in list of art media, art supplies. It is known for its brand ''Crayola'' and best known for its crayons. The company is headquartered in Forks Township, Northampton County, Pennsylvania, Forks Township, Pennsylvania in the Lehigh Valley region of the state. Since 1984, Crayola has been a Wholly Owned Subsidiary, wholly owned subsidiary of Hallmark Cards. Originally an industrial pigment supply company, Crayola soon shifted its focus to art products for home and school use, beginning with chalk, then crayons, followed later by colored pencils, marker pen, markers, paints, modeling clay, and other related goods. All Crayola-branded products are marketed as toxicity, nontoxic and safe for use by children. Most Crayola crayons are manufactured in the United States. Crayola also produces Silly Putty and a line of professional art products under the 'Portfolio Series brand', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Crayola Crayon Colors
Since the introduction of Crayola drawing crayons by Binney & Smith in 1903, more than 200 colors have been produced in a wide variety of assortments. The table below represents all of the colors found in regular Crayola assortments from 1903 to the present. Since the introduction of fluorescent crayons in the 1970s, the standard colors have been complemented by a number of specialty crayon assortments, represented in subsequent tables. Standard colors Specialty crayons Along with the regular packs of crayons, there have been many specialty sets, including Silver Swirls, Gem Tones, Pearl Brite Crayons, Metallic FX Crayons, Magic Scent Crayons, Silly Scents, and more. Fluorescent crayons In 1972, Binney & Smith introduced eight Crayola fluorescent crayons, designed to fluoresce under black light. The following year, they were added to the 72-count box, which had previously contained two of the eight most-used colors, in place of the duplicate crayons. These crayons remained ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
English Language
English is a West Germanic language that developed in early medieval England and has since become a English as a lingua franca, global lingua franca. The namesake of the language is the Angles (tribe), Angles, one of the Germanic peoples that Anglo-Saxon settlement of Britain, migrated to Britain after its End of Roman rule in Britain, Roman occupiers left. English is the list of languages by total number of speakers, most spoken language in the world, primarily due to the global influences of the former British Empire (succeeded by the Commonwealth of Nations) and the United States. English is the list of languages by number of native speakers, third-most spoken native language, after Mandarin Chinese and Spanish language, Spanish; it is also the most widely learned second language in the world, with more second-language speakers than native speakers. English is either the official language or one of the official languages in list of countries and territories where English ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Oxide
An iron oxide is a chemical compound composed of iron and oxygen. Several iron oxides are recognized. Often they are non-stoichiometric. Ferric oxyhydroxides are a related class of compounds, perhaps the best known of which is rust. Iron oxides and oxyhydroxides are widespread in nature and play an important role in many geological and biological processes. They are used as iron ores, pigments, catalysts, and in thermite, and occur in hemoglobin. Iron oxides are inexpensive and durable pigments in paints, coatings and colored concretes. Colors commonly available are in the " earthy" end of the yellow/orange/red/brown/black range. When used as a food coloring, it has E number E172. Stoichiometries Iron oxides feature as ferrous ( Fe(II)) or ferric ( Fe(III)) or both. They adopt octahedral or tetrahedral coordination geometry. Only a few oxides are significant at the earth's surface, particularly wüstite, magnetite, and hematite. * Oxides of FeII ** FeO: ir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laterite
Laterite is a soil type rich in iron and aluminium and is commonly considered to have formed in hot and wet tropical areas. Nearly all laterites are of rusty-red coloration, because of high iron oxide content. They develop by intensive and prolonged weathering of the underlying parent rock, usually when there are conditions of high temperatures and heavy rainfall with alternate wet and dry periods. The process of formation is called laterization. Tropical weathering is a prolonged process of chemical weathering which produces a wide variety in the thickness, grade, chemistry and ore mineralogy of the resulting soils. The majority of the land area containing laterites is between the tropics of Cancer and Capricorn. Laterite has commonly been referred to as a soil type as well as being a rock type. This, and further variation in the modes of conceptualizing about laterite (e.g. also as a complete weathering profile or theory about weathering), has led to calls for the term to be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
