"Ore An ore is an occurrence of rock or sediment that contains sufficient minerals with economically important elements, typically metals, that can be economically extracted from the deposit. The ores are extracted from the earth through mining; they are then refined (often via smelting) to extract the valuable element, or elements. The ore grade, or concentration of an ore mineral or metal, as well as its form of occurrence, will directly affect the costs associated with mining the ore. The cost of extraction must thus be weighed against the metal value contained in the rock to determine what ore can"
"Mineral processing In the field of extractive metallurgy, mineral processing, also known as ore dressing, is the process of separating commercially valuable minerals from their ores. Before the advent of heavy machinery the raw ore was broken up using hammers wielded by hand, a process called ""spalling"". Before long, mechanical means were found to achieve this. For instance, stamp mills were used in Samarkand as early as 973. They were also in use in medieval Persia. By the 11th century, stamp mills were in widespread use throughout the medieval Islamic world, from Islamic Spain and North Africa in the west"
"Smelting Smelting is a process of applying heat to ore in order to extract out a base metal. It is a form of extractive metallurgy. It is used to extract many metals from their ores, including silver, iron, copper, and other base metals. Smelting uses heat and a chemical reducing agent to decompose the ore, driving off other elements as gases or slag and leaving the metal base behind. The reducing agent is commonly a source of carbon, such as coke—or, in earlier times, charcoal. The carbon (or carbon monoxide derived from it) removes oxygen from the ore, leaving the"
"soil acidification and the acidification of aquatic environments. Smelting Smelting is a process of applying heat to ore in order to extract out a base metal. It is a form of extractive metallurgy. It is used to extract many metals from their ores, including silver, iron, copper, and other base metals. Smelting uses heat and a chemical reducing agent to decompose the ore, driving off other elements as gases or slag and leaving the metal base behind. The reducing agent is commonly a source of carbon, such as coke—or, in earlier times, charcoal. The carbon (or carbon monoxide derived from"
"the mining process. During hydraulic mining when the water, slurry, and debris flowed over the sluices and drainage tunnels, the particles were also mixed with liquid mercury. The mercury was used during the extraction period during the mining process. The mercury was used to attract the gold and sometimes silver from the mining ore, for extraction. The most common use of mercury for the extraction was a process called mercury amalgamation. The way that this process works is that the miner mixes the element mercury with mining silt or ore, the mercury then sticks to the gold, thus separating from"
"Heap leaching Heap leaching is an industrial mining process to extract precious metals, copper, uranium, and other compounds from ore via a series of chemical reactions that absorb specific minerals and then re-separates them after their division from other earth materials. Similar to ""in situ"" mining, heap leach mining differs in that it places ore on a liner, then adds the chemicals via drip systems to the ore, whereas ""in situ"" mining lacks these liners and pulls pregnant solution up to obtain the minerals. Most mining companies favor the economic feasibility of heap leaching, considering that heap leaching is a"
"subsurface mines. In some cases, the sale price of the metal/s involved make it economically feasible to mine lower concentration sources. Once the ore is mined, the metals must be extracted, usually by chemical or electrolytic reduction. Pyrometallurgy uses high temperatures to convert ore into raw metals, while hydrometallurgy employs aqueous chemistry for the same purpose. The methods used depend on the metal and their contaminants. When a metal ore is an ionic compound of that metal and a non-metal, the ore must usually be smelted—heated with a reducing agent—to extract the pure metal. Many common metals, such as iron,"
"Roasting (metallurgy) Roasting is a process of heating of sulfide ore to a high temperature in presence of air. It is a step of the processing of certain ores. More specifically, roasting is a metallurgical process involving gas–solid reactions at elevated temperatures with the goal of purifying the metal component(s). Often before roasting, the ore has already been partially purified, e.g. by froth flotation. The concentrate is mixed with other materials to facilitate the process. The technology is useful but is also a serious source of air pollution. Roasting consists of thermal gas–solid reactions, which can include oxidation, reduction, chlorination,"
"minerals' melting points. Since the gold is usually the heaviest of these minerals, it allows for concentrating the gold on the bottom of the crucible. The process requires considerably less heat than conventional refining methods, which can be obtainable even in remote locations (using charcoal). After the ore is crushed into a fine powder, it's lightly panned to leave only the heaviest minerals in the pan. It's then thoroughly mixed by three times (by volume) as much of borax and a few drops of water. This mixture is then heated until the whole mixture is molten, after which molten droplets"
"the ore and silt, forming one solid piece of mercury–gold amalgam. Additional separation from the silt and ore is done by washing away the ore with water until only the amalgam is left. The next step of the process is to separate the actual gold form the now useless mercury. The way this is done, is the miners heat up the mercury-gold amalgam to high temperature to vaporize the mercury away, leaving only the highly desired gold. The vaporization of mercury requires a temperature of at least 357 °C. In addition to the mercury-gold amalgam some residue mercury is also"
"Mineralization (geology) In geology, mineralization is the deposition of economically important metals in the formation of ore bodies or ""lodes"" by various process. The first scientific studies of this process took place in the English county of Cornwall by J.W.Henwood FRS and later by R.W. Fox, FRS. The term can also refer to the process by which waterborne minerals, such as calcium carbonate (calcite), iron oxide (hematite or limonite) or silica (quartz), replace organic material within the body of an organism that has died and was buried by sediments. Mineralization may also refer to the product resulting from the process"
"of mineralization. For example, mineralization (the process) may introduce metals (such as iron) into a rock. That rock may then be referred to as possessing iron mineralization. Mineralization (geology) In geology, mineralization is the deposition of economically important metals in the formation of ore bodies or ""lodes"" by various process. The first scientific studies of this process took place in the English county of Cornwall by J.W.Henwood FRS and later by R.W. Fox, FRS. The term can also refer to the process by which waterborne minerals, such as calcium carbonate (calcite), iron oxide (hematite or limonite) or silica (quartz), replace"
"to reject more of the undesirable minerals that also reported to the froth, in a process known as ""cleaning"". The product of cleaning is known as the ""cleaner concentrate"" or the ""final concentrate"". The objective of cleaning is to produce as high a concentrate grade as possible. The rougher concentrate is often subject to further grinding (usually called ""regrinding"") to get more complete liberation of the valuable minerals. Because it is a smaller mass than that of the original ore, less energy is needed than would be necessary if the whole ore were reground. Regrinding is often undertaken in specialized"
"is a process of extracting a metal from its ores by heating ores in a reducing environment such as a furnace. Smelting is a standard method for treating copper ores which are heated to melting point where the higher density copper metal is separated from the lighter ore. At the Adolphus William, two chimneys were built to provide the necessary draught for smelting ore with wood to fuel the furnace sourced from throughout the local area. Two small reverberatory furnaces were installed at the smelter. The reverberatory furnace was the predominant copper smelter technology in use in central Queensland and"
"of water jets to wash away either overburden or the ore itself. Blasting:<br> Explosives are used to break up a rock formation and aid in the collection of ore in a process called blasting. Blasting utilizes the heat and immense pressure of the detonated explosives to shatter and fracture a rock mass. The type of explosives used in mining are high explosives which vary in composition and performance properties. The mining engineer is responsible for the selection and proper placement of these explosives, in order to maximize efficiency and safety. Blasting occurs in many phases of the mining process, such"
"Mineral hydration Mineral hydration is an inorganic chemical reaction where water is added to the crystal structure of a mineral, usually creating a new mineral, usually called a ""hydrate"". In geological terms, the process of mineral hydration is known as ""retrograde alteration"" and is a process occurring in retrograde metamorphism. It commonly accompanies metasomatism and is often a feature of wall rock alteration around ore bodies. Hydration of minerals occurs generally in concert with hydrothermal circulation which may be driven by tectonic or igneous activity. There are two main ways in which minerals hydrate. One is conversion of an oxide"
"operate at this temperature without an external heat source. Pressure oxidation Pressure Oxidation is a process for extracting gold from refractory ore. The most common refractory ores are pyrite and arsenopyrite, which are sulfide ores that trap the gold within them. Refractory ores require pre-treatment before the gold can be adequately extracted. The pressure oxidation process is used to prepare such ores for conventional gold extraction processes such as cyanidation. It is performed in an autoclave at high pressure and temperature, where high-purity oxygen mixes with a slurry of ore. When the original sulfide minerals are oxidized at high temperature"
"Pyroprocessing Pyroprocessing (from Greek Πυρος = ""fire"") is a process in which materials are subjected to high temperatures (typically over 800 °C) in order to bring about a chemical or physical change. Pyroprocessing includes such terms as ore-roasting, calcination and sintering. Equipment for pyroprocessing includes kilns, electric arc furnaces and reverberatory furnaces. Cement manufacturing is a very common example of pyroprocessing. The raw material mix (raw meal) is fed to a kiln where pyroprocessing takes place. As with most industries, pyroprocessing is the most energy-intensive part of the industrial process. Argonne National Laboratory pioneered the development of pyrochemical processing, or"
"Mining Mining is the extraction of valuable minerals or other geological materials from the earth, usually from an orebody, lode, vein, seam, reef or placer deposit. These deposits form a mineralized package that is of economic interest to the miner. Ores recovered by mining include metals, coal, oil shale, gemstones, limestone, chalk, dimension stone, rock salt, potash, gravel, and clay. Mining is required to obtain any material that cannot be grown through agricultural processes, or created artificially in a laboratory or factory. Mining in a wider sense includes extraction of any non-renewable resource such as petroleum, natural gas, or even"
"Cupellation Cupellation is a refining process in metallurgy, where ores or alloyed metals are treated under very high temperatures and have controlled operations to separate noble metals, like gold and silver, from base metals like lead, copper, zinc, arsenic, antimony or bismuth, present in the ore. The process is based on the principle that precious metals do not oxidise or react chemically, unlike the base metals; so when they are heated at high temperatures, the precious metals remain apart and the others react forming slags or other compounds. Since the Early Bronze Age, the process was used to obtain silver"
"be processed and what ore is of too low a grade to be worth mining. Metal ores are generally oxides, sulfides, silicates, or native metals (such as native copper) that are not commonly concentrated in the Earth's crust, or noble metals (not usually forming compounds) such as gold. The ores must be processed to extract the elements of interest from the waste rock and from the ore minerals. Ore bodies are formed by a variety of geological processes. The process of ore formation is called ore genesis. An ore deposit is an accumulation of ore. This is distinct from a"
"volume of the ore rock. A key objective in the metallurgical treatment of any ore is the separation of ore minerals from gangue minerals within the rock. The first stage of any process within a metallurgical treatment circuit is accurate grinding or ""comminution"", where the rock is crushed to produce small particles (<100 μm) consisting of individual mineral phases. These particles are then separated to remove gangue (rocks residues), thereafter followed by a process of physical liberation of the ore minerals from the rock. The process of liberation of copper ores depends upon whether they are oxide or sulfide ores."
"auxiliary materials handling operations are also considered a branch of mineral processing such as storage (as in bin design), conveying, sampling, weighing, slurry transport, and pneumatic transport. The efficiency and efficacy of many processing techniques are influenced by upstream activities such as mining method and blending. Mineral processing In the field of extractive metallurgy, mineral processing, also known as ore dressing, is the process of separating commercially valuable minerals from their ores. Before the advent of heavy machinery the raw ore was broken up using hammers wielded by hand, a process called ""spalling"". Before long, mechanical means were found to"
"Another method is electrolysis of ferrous chloride onto an iron cathode. Industrial iron production starts with iron ores, principally hematite, which has a nominal formula FeO, and magnetite, with the formula FeO. These ores are reduced to the metal in a carbothermic reaction, i.e. by treatment with carbon. The conversion is typically conducted in a blast furnace at temperatures of about 2000 °C. Carbon is provided in the form of coke. The process also contains a flux such as limestone, which is used to remove silicaceous minerals in the ore, which would otherwise clog the furnace. The coke and limestone"
"method is employed to remove the mineral. Surface mining comprises 90% of the world's mineral tonnage output. Also called open pit mining, surface mining is removing minerals in formations that are at or near the surface. Ore retrieval is done by material removal from the land in its natural state. Surface mining often alters the land characteristics, shape, topography, and geological make-up. Surface mining involves quarrying which is excavating minerals by means of machinery such as cutting, cleaving, and breaking. Explosives are usually used to facilitate breakage. Hard rocks such as limestone, sand, gravel, and slate are generally quarried into"
"Superior multimineral process The Superior multimineral process (also known as the McDowell–Wellman process or circular grate process) is an above ground shale oil extraction technology designed for production of shale oil, a type of synthetic crude oil. The process heats oil shale in a sealed horizontal segmented vessel (retort) causing its decomposition into shale oil, oil shale gas and spent residue. The particularities of this process is a recovery of saline minerals from the oil shale, and a doughnut-shape of the retort. The process is suitable for processing of mineral-rich oil shales, such as in the Piceance Basin. It has"
"state in commercially significant quantities. These minerals are primarily carbonates, sulfides, or oxides of the metal, mixed with other components such as silica and alumina. Roasting the carbonate and sulfide minerals in air converts them to oxides. The oxides, in turn, are smelted into the metal. Carbon monoxide was (and is) the reducing agent of choice for smelting. It is easily produced during the heating process, and as a gas comes into intimate contact with the ore. In the Old World, humans learned to smelt metals in prehistoric times, more than 8000 years ago. The discovery and use of the"
"is recovered either in its metallic state or as a chemical compound. This may include precipitation, distillation, adsorption, and solvent extraction. The final recovery step may involve precipitation, cementation, or an electrometallurgical process. Sometimes, hydrometallurgical processes may be carried out directly on the ore material without any pretreatment steps. More often, the ore must be pretreated by various mineral processing steps, and sometimes by pyrometallurgical processes. Pyrometallurgy involves high temperature processes where chemical reactions take place among gases, solids, and molten materials. Solids containing valuable metals are treated to form intermediate compounds for further processing or converted into their elemental"
"gold with the limonite of the resulting soils. While the first iron ore was likely meteoric iron, and hematite was far easier to smelt, in Africa, where the first evidence of iron metallurgy occurs, limonite is the most prevalent iron ore. Before smelting, as the ore was heated and the water driven off, more and more of the limonite was converted to hematite. The ore was then pounded as it was heated above 1250 °C, at which temperature the metallic iron begins sticking together and non-metallic impurities are thrown off as sparks. Complex systems developed, notably in Tanzania, to process"
"The ore was formed when the erupting magma became saturated in sulfur, forming globules of pentlandite, chalcopyrite, and other sulfides. These sulfides were then ""washed"" by the continuing torrent of erupting magma, and upgraded their tenor with nickel, copper, platinum, and palladium. The current resource known for these mineralised intrusions exceeds 1.8 billion tons. The ore is mined underground via several shafts, and a decline. The ore deposits are currently being extracted at greater than 1,200 m below ground. The ore deposits are drilled from the surface. The deposits are being explored using electromagnetic field geophysics, with detection loops on"
"Pressure oxidation Pressure Oxidation is a process for extracting gold from refractory ore. The most common refractory ores are pyrite and arsenopyrite, which are sulfide ores that trap the gold within them. Refractory ores require pre-treatment before the gold can be adequately extracted. The pressure oxidation process is used to prepare such ores for conventional gold extraction processes such as cyanidation. It is performed in an autoclave at high pressure and temperature, where high-purity oxygen mixes with a slurry of ore. When the original sulfide minerals are oxidized at high temperature and pressure, it completely releases the trapped gold. Pressure"
"mechanical means of crushing, grinding, and washing that enable the separation (extractive metallurgy) of valuable metals or minerals from their gangue (waste material). Processing of placer ore material consists of gravity-dependent methods of separation, such as sluice boxes. Only minor shaking or washing may be necessary to disaggregate (unclump) the sands or gravels before processing. Processing of ore from a lode mine, whether it is a surface or subsurface mine, requires that the rock ore be crushed and pulverized before extraction of the valuable minerals begins. After lode ore is crushed, recovery of the valuable minerals is done by one,"
"of its last radioactive waste, may take 100–150 years. Uranium mining is the process of extraction of uranium ore from the ground. A prominent use of uranium from mining is as fuel for nuclear power plants. After mining uranium ores, they are normally processed by grinding the ore materials to a uniform particle size and then treating the ore to extract the uranium by chemical leaching. The milling process commonly yields dry powder-form material consisting of natural uranium, ""yellowcake"", which is sold on the uranium market as UO, and uranium mining can use large amounts of water. The Church Rock"