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Carbonate-hosted Lead-zinc Ore Deposits
Carbonate-hosted lead-zinc ore deposits are important and highly valuable concentrations of lead and zinc sulfide ores hosted within carbonate (limestone, marl, dolomite) formations and which share a common genetic origin. These ore bodies range from 0.5 million tonnes of contained ore, to 20 million tonnes or more, and have a grade of between 4% combined lead and zinc to over 14% combined lead and zinc. These ore bodies tend to be compact, fairly uniform plug-like or pipe-like replacements of their host carbonate sequences and as such can be extremely profitable mines. This classification of ore deposits is also known as Mississippi Valley Type or MVT ore deposits, after a number of such deposits along the Mississippi River in the United States, where such ores were first recognised; these include the famed Southeast Missouri Lead District of southeastern Missouri, and deposits in northeast Iowa, southwest Wisconsin, and northwest Illinois. Similarly Irish-type carbonate l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lisheen Mine
Lisheen Mine is a former lead-zinc-silver mine located between the villages of Moyne and Templetuohy in County Tipperary, Ireland. In the Rathdowney Trend, Lisheen was an underground mine where the Lisheen deposit lies at an average depth of 170 metres (560 feet) below surface. The mine closed in 2015. Accidents and incidents The Lisheen Mine had two fatal accidents within two years. The first was an explosion in April 2011, and the second occurred on 4 April 2013 when a roof collapsed. In each case, a man died. History The Lisheen Deposit was discovered in April 1990 by Murray Hitzman who at the time was working for Chevron. A full feasibility study was conducted by SRK, Kilborn, and Kelsey Engineering and development of the mine began in 1997. In September 1999 the first (production) ore was brought to the surface and in December the first shipment of Zinc concentrates departed from the Port of Cork. Lisheen was expected to produce approximately 4.83 million dry metric tonne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supergene (geology)
In ore deposit geology, supergene processes or enrichment are those that occur relatively near the surface as opposed to deep hypogene processes. Supergene processes include the predominance of meteoric water circulation (i.e. water derived from precipitation) with concomitant Redox, oxidation and chemical weathering. The descending meteoric waters oxidize the primary (hypogene) Sulfide mineral, sulfide ore minerals and redistribute the metallic ore elements. Supergene ''enrichment'' occurs at the base of the oxidized portion of an ore deposit. Metals that have been leached from the oxidized ore are carried downward by percolating groundwater, and react with hypogene sulfides at the supergene-hypogene boundary. The reaction produces secondary sulfides with metal contents higher than those of the primary ore. This is particularly noted in copper ore deposits where the copper sulfide minerals chalcocite (Cu2S), covellite (CuS), digenite (Cu18S10), and djurleite (Cu31S16) are deposited ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrozincite
Hydrozincite, also known as zinc bloom or marionite, is a white carbonate mineral consisting of Zn5( CO3)2( OH)6. It is usually found in massive rather than crystalline form. It occurs as an oxidation product of zinc ores and as post mine incrustations. It occurs associated with smithsonite, hemimorphite, willemite, cerussite, aurichalcite, calcite and limonite. It was first described in 1853 for an occurrence in Bad Bleiberg, Carinthia, Austria Austria, formally the Republic of Austria, is a landlocked country in Central Europe, lying in the Eastern Alps. It is a federation of nine Federal states of Austria, states, of which the capital Vienna is the List of largest cities in Aust ... and named for its chemical content. References Mineral galleries data External links * Carbonate minerals Luminescent minerals Minerals described in 1853 Minerals in space group 12 Monoclinic minerals Zinc minerals {{carbonate-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smithsonite
Smithsonite, also known as zinc spar, is the mineral form of zinc carbonate ( Zn CO3). Historically, smithsonite was identified with hemimorphite before it was realized that they were two different minerals. The two minerals are very similar in appearance and the term calamine has been used for both, leading to some confusion. The distinct mineral smithsonite was named in 1832 by François Sulpice Beudant in honor of English scientist James Smithson (c. 1765–1829), who first identified the mineral in 1802. Smithsonite is a variably colored trigonal mineral which only rarely is found in well formed crystals. The typical habit is as earthy botryoidal masses. It has a Mohs hardness of 4.5 and a specific gravity of 4.4 to 4.5. Smithsonite occurs as a secondary mineral in the weathering or oxidation zone of zinc-bearing ore deposits. It sometimes occurs as replacement bodies in carbonate rocks and as such may constitute zinc ore. It commonly occurs in association with hemimorp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerussite
Cerussite (also known as lead carbonate or white lead ore) is a mineral consisting of lead carbonate with the chemical formula PbCO3, and is an important ore of lead. The name is from the Latin ''cerussa'', white lead. ''Cerussa nativa'' was mentioned by Conrad Gessner in 1565, and in 1832 F. S. Beudant applied the name ''céruse'' to the mineral, whilst the present form, cerussite, is due to W. Haidinger (1845). Miners' names in early use were lead-spar and white-lead-ore. Cerussite crystallizes in the orthorhombic crystal system and is isomorphous with aragonite. Like aragonite it is very frequently twinned, the compound crystals being pseudo-hexagonal in form. Three crystals are usually twinned together on two faces of the prism, producing six-rayed stellate groups with the individual crystals intercrossing at angles of nearly 60°. Crystals are of frequent occurrence and they usually have very bright and smooth faces. The mineral also occurs in compact granular masses, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anglesite
Anglesite is a lead sulfate mineral with the chemical formula PbSO4. It occurs as an oxidation product of primary lead sulfide ore, galena. Anglesite occurs as prismatic orthorhombic crystals and earthy masses, and is isomorphous with barite and celestine. It contains 74% of lead by mass and therefore has a high specific gravity of 6.3. Anglesite's color is white or gray with pale yellow streaks. It may be dark gray if impure. It was first recognized as a mineral species by William Withering in 1783, who discovered it in the Parys copper-mine in Anglesey; the name anglesite, from this locality, was given by F. S. Beudant in 1832. The crystals from Anglesey, which were formerly found abundantly on a matrix of dull limonite, are small in size and simple in form, being usually bounded by four faces of a prism and four faces of a dome; they are brownish-yellow in colour owing to a stain of limonite. Crystals from some other localities, notably from in Sardinia, are transparent a ... [...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 is now called 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marcasite
The mineral marcasite, sometimes called "white iron pyrite", is iron sulfide (FeS2) with orthorhombic crystal structure. It is physically and crystallographically distinct from pyrite, which is iron sulfide with cubic crystal structure. Both structures contain the disulfide S22− ion, having a short bonding distance between the sulfur atoms. The structures differ in how these di-anions are arranged around the Fe2+ cations. Marcasite is lighter and more brittle than pyrite. Specimens of marcasite often crumble and break up due to the unstable crystal structure. On fresh surfaces, it is pale yellow to almost white and has a bright metallic luster. It tarnishes to a yellowish or brownish color and gives a black streak. It is a brittle material that cannot be scratched with a knife. The thin, flat, tabular crystals, when joined in groups, are called "cockscombs". In the late medieval and early modern eras, the word "marcasite" meant all iron sulfides in general, including b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphalerite
Sphalerite 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 deposits, sedimentary exhalative, Carbonate-hosted lead-zinc ore deposits, Mississippi-Valley type, and Volcanogenic massive sulfide ore deposit, volcanogenic massive sulfide deposits. It is found in association with galena, chalcopyrite, pyrite (and other sulfide mineral, sulfides), calcite, dolomite (mineral), 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 ... [...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), cubic crystal system often showing octahedral forms. It is often associated with the minerals sphalerite, calcite and fluorite. As a pure specimen held in the hand, under standard temperature and pressure, galena is insoluble in water and so is almost non-toxic. Handling galena under these specific conditions (such as in a museum or as part of geology instruction) poses practically no risk; however, as lead(II) sulfide is reasonably reactive in a variety of environments, it can be highly toxic if swallowed or inhaled, particularly under prolonged or repeated exposure. Occurrence Galena is the main ore of lead, used since ancient times, since lead can be smelted from galena in an ordinary wood fire. G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bitumen
Bitumen ( , ) is an immensely viscosity, viscous constituent of petroleum. Depending on its exact composition, it can be a sticky, black liquid or an apparently solid mass that behaves as a liquid over very large time scales. In American English, the material is commonly referred to as asphalt or tar. Whether found in natural deposits or refined from petroleum, the substance is classed as a pitch (resin), pitch. Prior to the 20th century, the term asphaltum was in general use. The word derives from the Ancient Greek word (), which referred to natural bitumen or pitch. The largest natural deposit of bitumen in the world is the Pitch Lake of southwest Trinidad, which is estimated to contain 10 million tons. About 70% of annual bitumen production is destined for road surface, road construction, its primary use. In this application, bitumen is used to bind construction aggregate, aggregate particles like gravel and forms a substance referred to as asphalt concrete, which is collo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
