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Massive Sulfide Deposits
Massive sulfide deposits are ore deposits that have significant stratiform ore bodies consisting mainly of sulfide minerals. Most massive sulfide ore deposits have other portions that are not massive, including stringer or feeder zones beneath the massive parts that mostly consist of crosscutting veins and veinlets of sulfides in a matrix of pervasively altered host rock and gangue. The term "massive sulfide" is mainly applied to the following classes of ore deposits: * Volcanogenic massive sulfide ore deposits (VMS), also called volcanic-hosted massive sulfide deposits (VHMS) * Sedimentary exhalative deposits (SEDEX), also called sediment-hosted massive sulfide deposits The main sulfide minerals occurring in both classes of massive sulfide ores are pyrite and/or pyrrhotite and variable amounts of sphalerite, galena, and chalcopyrite. The term "massive sulfide deposit" became popular in the 1960s with the discovery of seafloor massive sulfide deposits Seafloor massive sulfide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ore Deposit
Ore is natural rock or sediment that contains one or more valuable minerals, typically containing metals, that can be mined, treated and sold at a profit.Encyclopædia Britannica. "Ore". Encyclopædia Britannica Online. Retrieved 7 April 2021Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology: American Geological Institute, 799 p. Ore is extracted from the earth through mining and treated or refined, often via smelting, to extract the valuable metals or minerals. The ''grade'' of ore refers to the concentration of the desired material it contains. The value of the metals or minerals a rock contains must be weighed against the cost of extraction to determine whether it is of sufficiently high grade to be worth mining, and is therefore considered an ore. Minerals of interest are generally oxides, sulfides, silicates, or native metals such as copper or gold. Ores must be processed to extract the elements of interest from the waste rock. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ore Body
Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the economic viability of investing in the equipment, labor, and energy required to extract, refine and transport the materials found at the mine to manufacturers who can use the material. 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 most materials that cannot be grown through agricultural processes, or feasibly 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 water. Modern mining processes involve prospecting for ore bodies, analysis of the profit potential of a proposed mine, extraction of the desired materials, and f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfide Mineral
The sulfide minerals are a class of minerals containing sulfide (S2−) or disulfide (S22−) as the major anion. Some sulfide minerals are economically important as metal ores. The sulfide class also includes the selenides, the tellurides, the arsenides, the 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 * Proustite * Tetrahedrite * Tennantite * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gangue
In mining, gangue () is the commercially worthless material that surrounds, or is closely mixed with, a wanted mineral in an ore deposit. It is thus distinct from overburden, which is the waste rock or materials overlying an ore or mineral body that are displaced during mining without being processed, and from tailings, which is rock already stripped of valuable minerals. The separation of valuable mineral from gangue minerals is known as mineral processing, mineral dressing, or ore dressing. It is a necessary, and often significant, aspect of mining. It can be a complicated process, depending on the nature of the minerals involved. For example, galena, an ore of lead, is usually found in large pieces within its gangue, so it does not normally need extensive processing to remove it; but cassiterite, the chief ore mineral of tin, is usually disseminated as very small crystals throughout its gangue, so when it is mined from hard rock, the ore-bearing rock first needs to be crush ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanogenic Massive Sulfide Ore Deposit
Volcanogenic massive sulfide ore deposits, also known as VMS ore deposits, are a type of metal sulfide ore deposit, mainly copper-zinc which are associated with and created by volcanic-associated hydrothermal events in submarine environments. These deposits are also sometimes called volcanic-hosted massive sulfide (VHMS) deposits. The density generally is 4500 kg/m3. They are predominantly stratiform accumulations of sulfide minerals that precipitate from hydrothermal fluids on or below the seafloor in a wide range of ancient and modern geological settings. In modern oceans they are synonymous with sulfurous plumes called black smokers. They occur within environments dominated by volcanic or volcanic derived (e.g., volcano-sedimentary) rocks, and the deposits are coeval and coincident with the formation of said volcanic rocks. As a class, they represent a significant source of the world's copper, zinc, lead, gold and silver ores, with cobalt, tin, barium, sulfur, selenium, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary Exhalative Deposits
Sedimentary exhalative deposits (SEDEX or SedEx deposits) are zinc-lead deposits originally interpreted to have been formed by discharge of metal-bearing basinal fluids onto the seafloor resulting in the precipitation of mainly stratiform ore, often with thin laminations of sulphide minerals. Goodfellow, W.D., Lydon, J.W. (2007) Sedimentary exhalative (SEDEX) deposits. In: Goodfellow, W.D. (Ed.) Mineral deposits of Canada: a synthesis of major deposit types, district metallogeny, the evolution of geological provinces, and exploration methods. Geological Association of Canada Special Publication 5, 163–183. SEDEX deposits are hosted largely by clastic rocks deposited in intracontinental rifts or failed rift basins and passive continental margins. Since these ore deposits frequently form massive sulfide lenses, they are also named ''sediment''-hosted massive sulfide (SHMS) deposits, as opposed to ''volcanic''-hosted massive sulfide (VHMS) deposits. The sedimentary appearance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrite
The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Fe S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of ''fool's gold''. The color has also led to the nicknames ''brass'', ''brazzle'', and ''Brazil'', primarily used to refer to pyrite found in coal. The name ''pyrite'' is derived from the Greek (), 'stone or mineral which strikes fire', in turn from (), 'fire'. In ancient Roman times, this name was applied to several types of stone that would create sparks when struck against steel; Pliny the Elder described one of them as being brassy, almost certainly a reference to what we now call pyrite. By Georgius Agricola's time, , the term had become a generic term for all of the sulfide minerals. Pyrite is usually found associated with other sulfides or oxides in quartz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrrhotite
Pyrrhotite is an iron sulfide mineral with the formula Fe(1-x)S (x = 0 to 0.2). It is a nonstoichiometric variant of FeS, the mineral known as troilite. Pyrrhotite is also called magnetic pyrite, because the color is similar to pyrite and it is weakly magnetic. The magnetism decreases as the iron content increases, and troilite is non-magnetic.Vaughan, D. J.; Craig, J. R. "Mineral Chemistry of Metal Sulfides" Cambridge University Press, Cambridge: 1978. . Structure Pyrrhotite exists as a number of polytypes of hexagonal or monoclinic crystal symmetry; several polytypes often occur within the same specimen. Their structure is based on the NiAs unit cell. As such, Fe occupies an octahedral site and the sulfide centers occupy trigonal prismatic sites. Materials with the NiAs structure often are non-stoichiometric because they lack up to 1/8th fraction of the metal ions, creating vacancies. One of such structures is pyrrhotite-4C (Fe7S8). Here "4" indicates that iron vacan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphalerite
Sphalerite (sometimes spelled sphaelerite) is a sulfide mineral with the chemical formula . It is the most important ore of zinc. Sphalerite is found in a variety of deposit types, but it is primarily in sedimentary exhalative, Mississippi-Valley type, and volcanogenic massive sulfide deposits. It is found in association with galena, chalcopyrite, pyrite (and other sulfides), calcite, dolomite, quartz, rhodochrosite, and fluorite. German geologist Ernst Friedrich Glocker discovered sphalerite in 1847, naming it based on the Greek word ''sphaleros'', meaning "deceiving", due to the difficulty of identifying the mineral. In addition to zinc, sphalerite is an ore of cadmium, gallium, germanium, and indium. Miners have been known to refer to sphalerite as ''zinc blende'', ''black-jack'', and ''ruby blende''. Marmatite is an opaque black variety with a high iron content. Crystal habit and structure Sphalerite crystallizes in the face-centered cubic zincblende crystal s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galena
Galena, also called lead glance, is the natural mineral form of lead(II) sulfide (PbS). It is the most important ore of lead and an important source of silver. Galena is one of the most abundant and widely distributed sulfide minerals. It crystallizes in the cubic crystal system often showing octahedral forms. It is often associated with the minerals sphalerite, calcite and fluorite. Occurrence Galena is the main ore of lead, used since ancient times, since lead can be smelted from galena in an ordinary wood fire. Galena typically is found in hydrothermal veins in association with sphalerite, marcasite, chalcopyrite, cerussite, anglesite, dolomite, calcite, quartz, barite, and fluorite. It is also found in association with sphalerite in low-temperature lead-zinc deposits within limestone beds. Minor amounts are found in contact metamorphic zones, in pegmatites, and disseminated in sedimentary rock. In some deposits the galena contains up to 0.5% silver, a byprodu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chalcopyrite
Chalcopyrite ( ) is a copper iron sulfide mineral and the most abundant copper ore mineral. It has the chemical formula CuFeS2 and crystallizes in the tetragonal system. It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mohs scale. Its streak is diagnostic as green-tinged black. On exposure to air, chalcopyrite tarnishes to a variety of oxides, hydroxides, and sulfates. Associated copper minerals include the sulfides bornite (Cu5FeS4), chalcocite (Cu2S), covellite (CuS), digenite (Cu9S5); carbonates such as malachite and azurite, and rarely oxides such as cuprite (Cu2O). Is rarely found in association with native copper. Chalcopyrite is a conductor of electricity. Etymology The name chalcopyrite comes from the Greek words , which means copper, and ', which means striking fire. It was sometimes historically referred to as "yellow copper". Identification Chalcopyrite is often confused with pyrite and gold since all three of these minerals have a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seafloor Massive Sulfide Deposits
Seafloor massive sulfide deposits or SMS deposits, are modern equivalents of ancient volcanogenic massive sulfide ore deposits or VMS deposits. The term has been coined by mineral explorers to differentiate the modern deposit from the ancient. SMS deposits were first recognized during the exploration of the deep oceans and the mid ocean ridge spreading centers in the early 1960s. Deep ocean research submersibles, bathyspheres and remote operated vehicles have visited and taken samples of black smoker chimneys, and it has been long recognised that such chimneys contain appreciable grades of Cu, Pb, Zn, Ag, Au and other trace metals. SMS deposits form in the deep ocean around submarine volcanic arcs, where hydrothermal vents exhale sulfide-rich mineralising fluids into the ocean. SMS deposits are laterally extensive and consist of a central vent mound around the area where the hydrothermal circulation exits, with a wide apron of unconsolidated sulfide silt or ooze which pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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