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Taconite
Taconite () is a variety of banded iron formation, an iron-bearing (over 15% iron) sedimentary rock, in which the iron minerals are interlayered with quartz, chert, or carbonate. The name ''taconyte'' was coined by Horace Vaughn Winchell (1865–1923) – son of Newton Horace Winchell, the Minnesota state geologist – during their pioneering investigations of the Precambrian Biwabik Iron Formation of northeastern Minnesota. He believed the sedimentary rock sequence hosting the iron-formation was correlative with the Taconic orogeny of New England, and referred to the unfamiliar and as-yet-unnamed iron-bearing rock as the 'taconic rock' or ''taconyte''. Following development of high grade direct shipping iron ore deposits on the Mesabi Range, containing up to 65% iron and as little as 1.25% silica, miners termed the unaltered iron-formation wall rock taconite. The iron content of taconite is generally 30% to 35%, and the silica content generally around 45%. Iron in taconite is c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesabi Iron Range
The Mesabi Iron Range is a mining district and mountain range in northeastern Minnesota following an elongate trend containing large deposits of iron ore. It is the largest of four major iron ranges in the region collectively known as the Iron Range of Minnesota. First described in 1866, it is the chief iron ore mining district in the United States. The district is located largely in Itasca and Saint Louis counties. It has been extensively worked since 1892, and has seen a transition from high-grade direct shipping ores through gravity concentrates to the current industry exclusively producing iron ore (taconite) pellets. Production has been dominantly controlled by vertically integrated steelmakers since 1901, and therefore is dictated largely by US ironmaking capacity and demand. Name The Mesabi Range was known to the local Ojibwe as ('Giant mountain'). Throughout the Mesabi Range, ''Mesaba'' and ''Missabe'' spelling variations are found along with places containing ''Gi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edward Wilson Davis
Edward Wilson Davis (May 8, 1888 – December 3, 1973) was an American engineer and inventor famous for pioneering early research into taconite. As a researcher at the University of Minnesota, Davis developed an engineering process to economically extract iron ore from hard taconite rocks, making taconite valuable as iron ore for the iron and steel industries. He worked closely with industrial firms such as the Mesabi Iron Company and the Reserve Mining Company to transform his research into a working industry on northeast Minnesota's Iron Range. Davis was known as "Mr. Taconite" for his efforts. History Davis was born on May 8, 1888, in Cambridge City, Indiana. He pursued courses in science and engineering and received a degree in electrical engineering from Purdue University in 1911. In 1912, Davis began working as a mathematics instructor at the University of Minnesota. In 1913, Davis began working on taconite. Over the next four decades, Davis devised a process to crush ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Ore
Iron ores are rocks and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and vary in color from dark grey, bright yellow, or deep purple to rusty red. The iron is usually found in the form of magnetite (, 72.4% Fe), hematite (, 69.9% Fe), goethite (, 62.9% Fe), limonite (, 55% Fe), or siderite (, 48.2% Fe). Ores containing very high quantities of hematite or magnetite (typically greater than about 60% iron) are known as natural ore or irect shipping ore and can be fed directly into iron-making blast furnaces. Iron ore is the raw material used to make pig iron, which is one of the main raw materials to make steel — 98% of the mined iron ore is used to make steel. In 2011 the ''Financial Times'' quoted Christopher LaFemina, mining analyst at Barclays Capital, saying that iron ore is "more integral to the global economy than any other commodity, except perhaps oil". Sources Elemental iron is virtually absent o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Banded Iron Formation
Banded iron formations (BIFs; also called banded ironstone formations) are distinctive units of sedimentary rock consisting of alternating layers of iron oxides and iron-poor chert. They can be up to several hundred meters in thickness and extend laterally for several hundred kilometers. Almost all of these formations are of Precambrian age and are thought to record the Great Oxygenation Event, oxygenation of the Earth's oceans. Some of the Earth's oldest rock formations, which formed about (Year#SI prefix multipliers, Ma), are associated with banded iron formations. Banded iron formations are thought to have formed in sea water as the result of oxygen production by photosynthesis, photosynthetic cyanobacteria. The oxygen combined with dissolved iron in Earth's oceans to form insoluble iron oxides, which precipitated out, forming a thin layer on the ocean floor. Each band is similar to a varve, resulting from cyclic variations in oxygen production. Banded iron formations we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Minnesota
The University of Minnesota Twin Cities (historically known as University of Minnesota) is a public university, public Land-grant university, land-grant research university in the Minneapolis–Saint Paul, Twin Cities of Minneapolis and Saint Paul, Minnesota, United States. It is the Flagship#Colleges and universities in the United States, flagship institution of the University of Minnesota System and is organized into 19 colleges, schools, and other major academic units. The Twin Cities campus is the oldest and largest in the University of Minnesota system and has the List of United States university campuses by enrollment, ninth-largest (as of the 2022–2023 academic year) main campus student body in the United States, with 54,890 students at the start of the 2023–24 academic year. The campus comprises locations in Minneapolis and Falcon Heights, Minnesota, Falcon Heights, a suburb of St. Paul, approximately apart. The Minnesota Territorial Legislature drafted a charter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minnesota
Minnesota ( ) is a U.S. state, state in the Upper Midwestern region of the United States. It is bordered by the Canadian provinces of Manitoba and Ontario to the north and east and by the U.S. states of Wisconsin to the east, Iowa to the south, and North Dakota and South Dakota to the west. It is the List of U.S. states and territories by area, 12th-largest U.S. state in area and the List of U.S. states and territories by population, 22nd-most populous, with about 5.8 million residents. Minnesota is known as the "Land of 10,000 Lakes"; it has 14,420 bodies of fresh water covering at least ten acres each. Roughly a third of the state is Forest cover by state and territory in the United States, forested. Much of the remainder is prairie and farmland. More than 60% of Minnesotans (about 3.71 million) live in the Minneapolis–Saint Paul metropolitan area, known as the "Twin Cities", which is Minnesota's main Politics of Minnesota, political, Economy of Minnesota, economic, and C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bentonite
Bentonite ( ) is an Absorption (chemistry), absorbent swelling clay consisting mostly of montmorillonite (a type of smectite) which can either be Na-montmorillonite or Ca-montmorillonite. Na-montmorillonite has a considerably greater swelling capacity than Ca-montmorillonite. Bentonite usually forms from the weathering of volcanic ash in seawater, or by hydrothermal circulation through the porosity of volcanic ash beds, which converts (devitrification) the volcanic glass (obsidian, rhyolite, dacite) present in the ash into clay minerals. In the mineral alteration process, a large fraction (up to 40–50 wt.%) of amorphous silica is dissolution (chemistry), dissolved and leaching (agriculture), leached away, leaving the bentonite deposit in place. Bentonite beds are white or pale blue or green (traces of redox, reduced ) in fresh exposures, turning to a cream color and then yellow, red, or brown (traces of oxidation, oxidized ) as the exposure is weathered further. As a swel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetite
Magnetite is a mineral and one of the main iron ores, with the chemical formula . It is one of the iron oxide, oxides of iron, and is ferrimagnetism, ferrimagnetic; it is attracted to a magnet and can be magnetization, magnetized to become a permanent magnet itself. With the exception of extremely rare native iron deposits, it is the most magnetic of all the naturally occurring minerals on Earth. Naturally magnetized pieces of magnetite, called lodestone, will attract small pieces of iron, which is how ancient peoples first discovered the property of magnetism. Magnetite is black or brownish-black with a metallic luster, has a Mohs scale of mineral hardness, Mohs hardness of 5–6 and leaves a black streak (mineralogy), streak. Small grains of magnetite are very common in igneous rocks, igneous and metamorphic rocks. The chemical IUPAC name is iron(II,III) oxide and the common chemical name is ''ferrous-ferric oxide''. Properties In addition to igneous rocks, magnetite als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Superior
Lake Superior is the largest freshwater lake in the world by surface areaThe Caspian Sea is the largest lake, but is saline, not freshwater. Lake Michigan–Huron has a larger combined surface area than Superior, but is normally considered two separate lakes. and the third-largest freshwater lake by volume, holding 10% of the fresh water in all of the world's rivers and lakes. Located in central North America, it is the northernmost and westernmost of the Great Lakes of North America, straddling the Canada–United States border with the Canadian province of Ontario to the north and east and the U.S. states of Minnesota to the west and Michigan and Wisconsin to the south. It drains into Lake Huron via St. Marys River, then through the lower Great Lakes to the St. Lawrence River and ultimately the Atlantic Ocean. Name The Ojibwe name for the lake is ''gichi-gami'' (in syllabics: , pronounced ''gitchi-gami'' or ''kitchi-gami'' in different dialects), meaning "great sea". ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blast Furnace
A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron, but also others such as lead or copper. ''Blast'' refers to the combustion air being supplied above atmospheric pressure. In a blast furnace, fuel ( coke), ores, and flux (limestone) are continuously supplied through the top of the furnace, while a hot blast of (sometimes oxygen enriched) air is blown into the lower section of the furnace through a series of pipes called tuyeres, so that the chemical reactions take place throughout the furnace as the material falls downward. The end products are usually molten metal and slag phases tapped from the bottom, and flue gases exiting from the top. The downward flow of the ore along with the flux in contact with an upflow of hot, carbon monoxide-rich combustion gases is a countercurrent exchange and chemical reaction process. In contrast, air furnaces (such as reverberatory furnaces) are naturally aspirated, usu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidize
Redox ( , , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of the reactants change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. The oxidation and reduction processes occur simultaneously in the chemical reaction. There are two classes of redox reactions: * Electron-transfer – Only one (usually) electron flows from the atom, ion, or molecule being oxidized to the atom, ion, or molecule that is reduced. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * Atom transfer – An atom transfers from one substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously, the oxidation state of oxygen decreases as it accepts electrons released by the iron. Although oxidatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
