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Orpiment
Orpiment, also known as ″yellow arsenic blende″ is a deep-colored, orange-yellow arsenic sulfide mineral with formula . It is found in volcanic fumaroles, low-temperature hydrothermal veins, and hot springs and may be formed through sublimation (phase transition), sublimation. Orpiment takes its name from the Latin ''auripigmentum'' (''aurum'', "gold" + ''pigmentum'', "pigment"), due to its deep-yellow color. Orpiment once was widely used in artworks, medicine, and other applications. Because of its toxicity and instability, its usage has declined. Etymology The Latin ''auripigmentum'' (''aurum'', "gold" + ''pigmentum'', "pigment") referred both to its deep-yellow color and to the historical belief that it was thought to contain gold. The Latin term was used by Pliny the Elder, Pliny in the first century CE. The Greek for orpiment was ''arsenikon'', deriving from the Greek word ''arsenikos'', meaning "male", from the belief that metals were of different sexes. This Greek te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orpiment - Streak Color
Orpiment, also known as ″yellow arsenic blende″ is a deep-colored, orange-yellow arsenic sulfide mineral with formula . It is found in volcanic fumaroles, low-temperature hydrothermal veins, and hot springs and may be formed through sublimation. Orpiment takes its name from the Latin ''auripigmentum'' (''aurum'', "gold" + ''pigmentum'', "pigment"), due to its deep-yellow color. Orpiment once was widely used in artworks, medicine, and other applications. Because of its toxicity and instability, its usage has declined. Etymology The Latin ''auripigmentum'' (''aurum'', "gold" + ''pigmentum'', "pigment") referred both to its deep-yellow color and to the historical belief that it was thought to contain gold. The Latin term was used by Pliny in the first century CE. The Greek for orpiment was ''arsenikon'', deriving from the Greek word ''arsenikos'', meaning "male", from the belief that metals were of different sexes. This Greek term was used by Theophrastus in the fourth cent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsenic Blende
Arsenic blende or ''Arsenblende'' () is a trivial name that has partially fallen out of scientific use, used by mineralogists, as well as representatives of mining and craft professions in relation to at least two similar ore minerals — orpiment and realgar,''Krivovichev V. G.'' Mineralogical glossary. Scientific editor A. G. Bulakh. — St.Petersburg: St.Petersburg Univ. Publ. House. 2009. — 556 p. — ISBN 978-5-288-04863-0 in composition — arsenic sulfides. History of the term Both of these minerals, realgar and orpiment, have been mined for a very long time, for thousands of years. They were mined as natural dyes, as medicinal agents, and as preparations that were important in alchemical practice. Their use as pigments was very significant, both in pure form and in mixed form; for example, orpiment was constantly required to make up the green dye that was used to dye wool in the Middle Ages in Western Europe. Arsenic blende was used even more widely in medicine; for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Realgar
Realgar ( ), also known as arsenic blende, ruby sulphur or ruby of arsenic, is an arsenic sulfide mineral with the chemical formula α-. It is a soft, sectile mineral occurring in monoclinic crystals, or in granular, compact, or powdery form, often in association with the related mineral, orpiment (). It is orange-red in color, melts at 320 °C, and burns with a bluish flame releasing fumes of arsenic and sulfur. Realgar is soft with a Mohs hardness of 1.5 to 2 and has a specific gravity of 3.5. Its streak is orange colored. It is trimorphous with pararealgar and bonazziite. Etymology Its name comes from the Arabic ''rahj al-ġār'' ( , "powder of the mine"), via Medieval Latin, and its earliest record in English is in the 1390s. Uses Realgar is a minor ore of arsenic extracted in China, Peru, and the Philippines. Historical uses Realgar was used by firework manufacturers to create the color white in fireworks prior to the availability of powdered metals such as al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Realgar And Orpiment-2
Realgar ( ), also known as arsenic blende, ruby sulphur or ruby of arsenic, is an arsenic sulfide mineral with the chemical formula α-. It is a soft, sectile mineral occurring in monoclinic crystals, or in granular, compact, or powdery form, often in association with the related mineral, orpiment (). It is orange-red in color, melts at 320 °C, and burns with a bluish flame releasing fumes of arsenic and sulfur. Realgar is soft with a Mohs hardness of 1.5 to 2 and has a specific gravity of 3.5. Its streak is orange colored. It is trimorphous with pararealgar and bonazziite. Etymology Its name comes from the Arabic ''rahj al-ġār'' ( , "powder of the mine"), via Medieval Latin, and its earliest record in English is in the 1390s. Uses Realgar is a minor ore of arsenic extracted in China, Peru, and the Philippines. Historical uses Realgar was used by firework manufacturers to create the color white in fireworks prior to the availability of powdered metals such as alumi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsenic
Arsenic is a chemical element; it has Symbol (chemistry), symbol As and atomic number 33. It is a metalloid and one of the pnictogens, and therefore shares many properties with its group 15 neighbors phosphorus and antimony. Arsenic is notoriously toxic. It occurs naturally in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. It has various Allotropes of arsenic, allotropes, but only the grey form, which has a metallic appearance, is important to industry. The primary use of arsenic is in alloys of lead (for example, in car batteries and ammunition). Arsenic is also a common n-type dopant in semiconductor electronic devices, and a component of the III–V compound semiconductor gallium arsenide. Arsenic and its compounds, especially the trioxide, are used in the production of pesticides, treated wood products, herbicides, and insecticides. These applications are declining with the increasing recognition of the persistent tox ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfide Mineral
The sulfide minerals are a class of minerals containing sulfide (S2−) or disulfide () as the major anion. Some sulfide minerals are economically important as metal ores. The sulfide class also includes the selenide mineral, selenides, the telluride mineral, tellurides, the arsenide mineral, arsenides, the antimonide mineral, antimonides, the bismuthinides, the sulfarsenides and the sulfosalts.http://www.minerals.net/mineral/sort-met.hod/group/sulfgrp.htm Minerals.net Dana Classification, SulfidesKlein, Cornelis and Cornelius S. Hurlbut, Jr., 1986, ''Manual of Mineralogy'', Wiley, 20th ed., pp 269-293 Sulfide minerals are inorganic compounds. Minerals Common or important examples include: * Acanthite *Chalcocite *Bornite *Galena *Sphalerite *Chalcopyrite *Pyrrhotite *Millerite *Pentlandite *Covellite *Cinnabar *Realgar *Orpiment *Stibnite *Pyrite *Marcasite *Molybdenite Sulfarsenides: *Cobaltite *Arsenopyrite *Gersdorffite Sulfosalts: *Pyrargyrite *Pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refractive Index
In optics, the refractive index (or refraction index) of an optical medium is the ratio of the apparent speed of light in the air or vacuum to the speed in the medium. The refractive index determines how much the path of light is bent, or refraction, refracted, when entering a material. This is described by Snell's law of refraction, , where and are the angle of incidence (optics), angle of incidence and angle of refraction, respectively, of a ray crossing the interface between two media with refractive indices and . The refractive indices also determine the amount of light that is reflectivity, reflected when reaching the interface, as well as the critical angle for total internal reflection, their intensity (Fresnel equations) and Brewster's angle. The refractive index, n, can be seen as the factor by which the speed and the wavelength of the radiation are reduced with respect to their vacuum values: the speed of light in a medium is , and similarly the wavelength in that me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Munsell Color System
The Munsell color system is a color space that specifies colors based on three properties of color: hue (basic color), value (lightness), and colorfulness, chroma (color intensity). It was created by Albert Henry Munsell, Albert H. Munsell in the first decade of the 20th century and adopted by the United States Department of Agriculture (USDA) as the official color system for soil research in the 1930s. Several earlier color order systems in the field of colorimetry had placed colors into a three-dimensional color solid of one form or another, but Munsell was the first to separate hue, value, and chroma into Color difference#Tolerance, perceptually uniform and independent dimensions, and he was the first to illustrate the colors systematically in three-dimensional space. Munsell's system, particularly the later renotations, is based on rigorous measurements of human subjects' color vision, visual responses to color, putting it on a firm experimental scientific basis. Because of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canary-yellow
Varieties of the color yellow may differ in hue, chroma (also called saturation, intensity, or colorfulness) or lightness (or value, tone, or brightness), or in two or three of these qualities. Variations in value are also called tints and shades, a tint being a yellow or other hue mixed with white, a shade being mixed with black. A large selection of these various colors is shown below. Web colors Yellow (RGB) (X11 yellow) (color wheel yellow) The color box at right shows the most intense yellow representable in 8-bit RGB color model; yellow is a ''secondary'' color in an additive RGB space. This color is also called color wheel yellow. It is at precisely 60 degrees on the HSV color wheel, also known as the RGB color wheel. Its complementary color is blue. Yellow (CMYK) (process yellow) (canary yellow) Process yellow (also called pigment yellow or printer's yellow), also known as canary yellow, is one of the three colors typically used as subtractive primary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoclinic Crystal System
In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic system. They form a parallelogram prism. Hence two pairs of vectors are perpendicular (meet at right angles), while the third pair makes an angle other than 90°. Bravais lattices Two monoclinic Bravais lattices exist: the primitive monoclinic and the base-centered monoclinic. For the base-centered monoclinic lattice, the primitive cell has the shape of an oblique rhombic prism;See , row mC, column Primitive, where the cell parameters are given as a1 = a2, α = β it can be constructed because the two-dimensional centered rectangular base layer can also be described with primitive rhombic axes. The length a of the primitive cell below equals \frac \sqrt of the conventional cell above. Crystal classes The table below organizes the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Botryoidal
A botryoidal ( ) texture or mineral habit, is one in which the mineral has an external form composed of many rounded segments, named for the Ancient Greek (), meaning "a bunch of grapes".Adjective form: ''botruoeidēs'' This is a common form for many minerals, particularly hematite and malachite, which are known for frequently forming botryoidal masses. It is also a common form of goethite, smithsonite, fluorite, and chrysocolla. Similar habits are ''reniform'' (kidney-shaped) and ''mammillary'' (breast-shaped or partial spheres). Formation Minerals take on a botryoidal habit when they form in an environment containing many nuclei, specks of sand, dust, or other particulate matter to serve as sources of crystal nucleation. Acicular or fibrous crystals grow outward from these "seeds" at the same or very similar rate, resulting in radial crystal growth. As these spheres grow, they can run into or overlap with others that are nearby, fusing together to form a botryoidal clu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal Habit
In mineralogy, crystal habit is the characteristic external shape of an individual crystal or aggregate of crystals. The habit of a crystal is dependent on its crystallographic form and growth conditions, which generally creates irregularities due to limited space in the Crystallization, crystallizing medium (commonly in Rock (geology), rocks).Klein, Cornelis, 2007, ''Minerals and Rocks: Exercises in Crystal and Mineral Chemistry, Crystallography, X-ray Powder Diffraction, Mineral and Rock Identification, and Ore Mineralogy,'' Wiley, third edition, Wenk, Hans-Rudolph and Andrei Bulakh, 2004, ''Minerals: Their Constitution and Origin,'' Cambridge, first edition, Crystal forms Recognizing the habit can aid in mineral identification and description, as the crystal habit is an external representation of the Crystal structure, internal ordered atomic arrangement. Most natural crystals, however, do not display ideal habits and are commonly malformed. Hence, it is also important to des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
