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Stibnite
Stibnite, sometimes called antimonite, is a sulfide mineral, a mineral form of antimony trisulfide ( Sb2 S3). It is a soft, metallic grey crystalline solid with an orthorhombic space group. It is the most important source for the metalloid antimony. The name is derived from the Greek through the Latin as the former name for the mineral and the element antimony. Structure Stibnite has a structure similar to that of arsenic trisulfide, As2S3. The Sb(III) centers, which are pyramidal and three-coordinate, are linked via bent two-coordinate sulfide ions. However, some studies suggest that the actual coordination polyhedra of antimony are SbS7, with (3+4) coordination at the M1 site and (5+2) at the M2 site. Some of the secondary bonds impart cohesion and are connected with packing. Stibnite is grey when fresh, but can turn superficially black due to oxidation in air. Properties The melting point of Sb2S3 is . The band gap is 1.88 eV at room temperature and it is a pho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antimony Trisulfide
Antimony trisulfide () is found in nature as the crystalline mineral stibnite and the amorphous red mineral (actually a mineraloid) metastibnite. It is manufactured for use in safety matches, military ammunition, explosives and fireworks. It is also used as friction materials in break lining. It is very important critical primer material for military applications and tracer bullets. It also is used in the production of ruby-colored glass and in plastics as a flame retardant. Historically the stibnite form was used as a grey pigment in paintings produced in the 16th century. In 1817, the dye and fabric chemist, John Mercer discovered the non-stoichiometric compound Antimony Orange (approximate formula ), the first good orange pigment available for cotton fabric printing. Antimony trisulfide was also used as the image sensitive photoconductor in vidicon camera tubes. It is a semiconductor A semiconductor is a material with electrical conductivity between that of a conduc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stibnite - Herja Mine, Maramures, Romania
Stibnite, sometimes called antimonite, is a sulfide mineral, a mineral form of antimony trisulfide ( Sb2 S3). It is a soft, metallic grey crystalline solid with an orthorhombic space group. It is the most important source for the metalloid antimony. The name is derived from the Greek through the Latin as the former name for the mineral and the element antimony. Structure Stibnite has a structure similar to that of arsenic trisulfide, As2S3. The Sb(III) centers, which are pyramidal and three-coordinate, are linked via bent two-coordinate sulfide ions. However, some studies suggest that the actual coordination polyhedra of antimony are SbS7, with (3+4) coordination at the M1 site and (5+2) at the M2 site. Some of the secondary bonds impart cohesion and are connected with packing. Stibnite is grey when fresh, but can turn superficially black due to oxidation in air. Properties The melting point of Sb2S3 is . The band gap is 1.88 eV at room temperature and it is a phot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antimony
Antimony is a chemical element; it has chemical symbol, symbol Sb () and atomic number 51. A lustrous grey metal or metalloid, it is found in nature mainly as the sulfide mineral stibnite (). Antimony compounds have been known since ancient times and were powdered for use as medicine and cosmetics, often known by the Arabic name Kohl (cosmetics), kohl. The earliest known description of this metalloid in the West was written in 1540 by Vannoccio Biringuccio. China is the largest producer of antimony and its compounds, with most production coming from the Xikuangshan Mine in Hunan. The industrial methods for refining antimony from stibnite are Roasting (metallurgy), roasting followed by carbothermic reaction, reduction with carbon, or direct reduction of stibnite with iron. The most common applications for metallic antimony are in alloys with lead and tin, which have improved properties for solders, Bullet, bullets, and plain bearings. It improves the rigidity of lead-alloy pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kohl (cosmetics)
Kohl is a cosmetic product traditionally made by crushing stibnite (antimony sulfide). Modern kohl formulations often contain galena (lead sulfide), and in some cases charcoal or other pigments. Kohl is similar to eyeliner, which was traditionally made from charcoal. Kohl is widely used in many cultures to contour or darken the eyelids and heighten beauty marks. Several studies have questioned the safety of kohl out of fear of lead poisoning. Additionally, importing kohl into the United States is banned. Etymology The Arabic name formed the Arabic root , "to apply kohl." Transliteration variants of Arabic dialectal pronunciation include or . The English word ' is a loan of the Arabic word (via Middle Latin and French, originally, in the sense "powder of antimony"; the modern meaning is from the 18th century). Middle East and North Africa Kohl has been worn traditionally since the Naqada III era () by Egyptians of all social classes, originally as protection against e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metalloid
A metalloid is a chemical element which has a preponderance of material property, properties in between, or that are a mixture of, those of metals and Nonmetal (chemistry), nonmetals. The word metalloid comes from the Latin language, Latin ''metallum'' ("metal") and the Greek language, Greek ''oeides'' ("resembling in form or appearance"). There is no standard definition of a metalloid and no complete agreement on which elements are metalloids. Despite the lack of specificity, the term remains in use in the literature. The six commonly recognised metalloids are boron, silicon, germanium, arsenic, antimony and tellurium. Five elements are less frequently so classified: carbon, aluminium, selenium, polonium and astatine. On a standard periodic table, all eleven elements are in a diagonal region of the p-block extending from boron at the upper left to astatine at lower right. Some periodic tables include a dividing line between metals and nonmetals, and the metalloids may be found cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfur
Sulfur ( American spelling and the preferred IUPAC name) or sulphur ( Commonwealth spelling) is a chemical element; it has symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with the chemical formula S8. Elemental sulfur is a bright yellow, crystalline solid at room temperature. Sulfur is the tenth most abundant element by mass in the universe and the fifth most common on Earth. Though sometimes found in pure, native form, sulfur on Earth usually occurs as sulfide and sulfate minerals. Being abundant in native form, sulfur was known in ancient times, being mentioned for its uses in ancient India, ancient Greece, China, and ancient Egypt. Historically and in literature sulfur is also called brimstone, which means "burning stone". Almost all elemental sulfur is produced as a byproduct of removing sulfur-containing contaminants from natural gas and petroleum.. Downloahere Th ... [...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] |
Pyrotechnic Star
Pyrotechnic stars are pellets of pyrotechnic composition which may contain metal powders, salts or other compounds that, when ignited, burn a certain color or make a certain spark effect. They are a part of all projectile-type fireworks. The most common is the aerial shell. When watching this firework, it will launch into the sky, burning a lifting charge. Once the shell has attained proper altitude, due to other mechanisms within the firework, it will ignite the stars. Procedure Stars are either rolled, pumped or cut. *Rolled stars are small cores of a hard material (often lead shot or an organic material such as mustard seeds or even cut stars) which are coated in a rotating mixer similar to a concrete mixer. First, water is sprayed on these cores. Then an amount of a pyrotechnic composition is placed into the mixer. As these two steps are repeated, the stars grow into a larger spherical shape. *Pumped stars are stars that have been pumped using a star pump. A dampened comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philosopher's Stone
The philosopher's stone is a mythic alchemical substance capable of turning base metals such as mercury into gold or silver; it was also known as "the tincture" and "the powder". Alchemists additionally believed that it could be used to make an elixir of life which made possible rejuvenation and immortality. For many centuries, it was the most sought-after goal in alchemy. The philosopher's stone was the central symbol of the mystical terminology of alchemy, symbolizing perfection at its finest, divine illumination, and heavenly bliss. Efforts to discover the philosopher's stone were known as the Magnum Opus ("Great Work"). Antiquity The earliest known written mention of the philosopher's stone is in the ''Cheirokmeta'' by Zosimos of Panopolis (). Alchemical writers assign a longer history. Elias Ashmole and the anonymous author of ''Gloria Mundi'' (1620) claim that its history goes back to Adam, who acquired the knowledge of the stone directly from God. This knowledge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George Starkey (alchemist)
George Starkey (1628–1665) was a Colonial American alchemist, medical practitioner, and writer of numerous commentaries and chemical treatises that were widely circulated in Western Europe and influenced prominent men of science, including Robert Boyle and Isaac Newton. After relocating from New England to London, England, in 1650, Starkey began writing under the pseudonym Eirenaeus Philalethes. Starkey remained in England and continued his career in medicine and alchemy until his death in the Great Plague of London in 1665. Early life Starkey was born in Bermuda, the first of at least five children of George Stirk, a Scottish minister and devoted Calvinist, and Elizabeth Painter. During his early years in Bermuda, Starkey displayed interest in natural history, as evidenced by his written entomological observations of various insects indigenous to Bermuda. After the death of his father in 1637, Starkey was sent to New England, where he continued his early education before enroll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
