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Hematite is the alteration product of many Fe-bearing minerals, especially, magnetite, siderite, and pyrite, and is precipitated in seas and lakes by chemical or organic processes. Its occurence may be attributed, but not limited, to intense weathering under normal and oxidizing environments. Sedimentary deposits of hematite may be extensive ...
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is a necessary ingredient of a conventional oil trap. What is the biggest environmental risk of mining? reactions between tailing piles and rainwater that pollute water sources and damage vegetation. Ore deposits. are rock units that have a significant concentration of metals. Chapter 12.
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The deposit alteration studies about 20-25pcs samples from intrusive and host rock showed in order of dominance, intermediate argillic, propylitic, advanced argillic, phyllic, silicification and gossan alteration zones. The dominant types of alteration on the project are hematite alteration and secondary mineralization of pyrite (Figure 8).
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RUSK COUNTY: Hematite is a component of the gossan cap with other secondary iron and copper minerals at the Flambeau deposit, near Ladysmith (May, 1977). — Hematite occurs as "massive, layered or irregularly finely crystalline material" and as "martite" pseudomorphs after magnetite in prospect pits in quartz-sericite schist in SW Sec ...
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Deposits of two distinct types are formed in these host rocks. Respectively they are described in Models 30b.2, reduced facies Cu and 30b.3, ... Oxidizing fluids produce albitic, hematite rocks depleted in base metals, calcium and potassium. Metamorphosed red beds may have a purple or ... Surface exposures may be completely leached. Secondary ...
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Both it and Carrapateena occur in a hematite-rich granite breccia complex in the Gawler Craton, overlain by approximately 300 metres of flat-lying sedimentary rocks of the Stuart Shelf geological province. ... (Tertiary to Recent) near-surface uranium concentrations in sediments or soils. These deposits usually have secondary cementing minerals ...
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Extensive secondary leaching and hydration-dehydration has led to classical colloidal textures. The gossan is a replacement after magnetite and siderite. ... the ore deposits and the pyroclastic rock suite.Vergenoeg is the end member of a series of genetically related fluorite-hematite deposits which are associated with the Bushveld granites.
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This result may be due to some deposits being still buried, extensive erosion of the layered deposits, or minor concentrations of hematite escaping detection by …
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About Hematite Hide. Fe2O3. Steel-grey to black in crystals and massively crystalline ores, dull to bright "rust-red" in earthy, compact, fine-grained material. Hematite Group. Originally named about 300-325 BCE by Theophrastus from the Greek, "αιματίτις λίθος" ("aematitis lithos") for "blood stone".
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The paragenesis, textures, and chemical compositions of secondary hematite in regional potassic altered rhyolites, four IOA deposits, the sedimentary iron deposit at Pilot Knob and the Boss IOCG deposit in SE Missouri were determined and compared to primary magnetite from the IOA and IOCG deposits. Magnetite is composed of elements …
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Secondary enrichment and redistribution of gold and iron in zones of the quartz-hematite-barite-carbonate veinlets are related to the intrusion of thick Cretaceous dikes and sills. ... An extremely low amount of sulfides is typical of this deposit and of the epithermal deposits of the Kedon volcanic belt in the southern part of the Omolon ...
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Well-crystallized specimens of bladed specular hematite and Cumberland-habit quartz are the most common minerals found. Noteworthy accessory crystallized minerals include barite, calcite, and goethite. All six deposits are relatively free of sulfides, so that secondary goethite formed from weathering of iron-rich carbonates at some sites.
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The iron from magnetite and hematite deposits is the source of the steel used almost universally through our modern society's physical infrastructure. Without these two ores, human society would literally not have made it to the Iron Age, much less to modern civilization. ... enough secondary grade iron ore remains that the rise and fall of ...
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Hematite is less soluble and denser than magnetite under typical secondary circuit conditions, therefore a layer of hematite on the surface of magnetite can reduce the FAC rate in SG feed water train [9]. This agrees with the higher resistance under oxidizing conditions [10]. But hematite deposit on SG tubes is believed to promote the
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[1] We have completed a regional analysis of the hematite deposit in Terra Meridiani and conclude that the unit is in the midst of a 600-m-thick stack of friable layered materials superposed on Middle and Late Noachian cratered terrain. The deposits resemble terrestrial pyroclastics in the fact that they are: (1) thin, parallel bedded …
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Huge deposits of hematite are found in banded iron formations. ... Hematite can also occur without water, however, usually as the result of volcanic activity. Clay-sized hematite crystals can also occur as a …
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Abstract and Figures. This paper presents a first summary of results of an ongoing study, started some two years ago, of high-grade iron ore deposits in South Africa, India and Brazil, including a ...
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The black shale-hosted selenide vein-type deposit at Tilkerode, eastern Harz, Germany, has specular hematite enclosed in clausthalite (PbSe). The specular hematite has Ti and V in amounts of up to ∼1 wt.% TiO 2 and ∼3 wt.% V 2 O 5, and subordinate, but important, contents of Mo (22–372 ppm) and B (up to 68 ppm).The …
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The resulting deposits, known as laterites, are characterized by their distinctive red or brown color due to the prevalence of iron oxides, particularly hematite and goethite. Key characteristics of lateritic deposits include their highly weathered and porous nature, with a tendency to form in regions with high temperatures and heavy rainfall.
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Iron oxide minerals such as hematite and magnetite can provide valuable information on ore genesis. Uraniumbearing hematite has been proposed as a potential Pb-Pb chronometer for iron oxide copper-gold (IOCG) systems and allows for the direct dating of mineralization in oxide-rich hydrothermal deposits for which other suitable dating …
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Hydrothermal magnetite from the Starra iron oxide‑copper gold (IOCG) deposit in northwest Queensland, Australia, records a gradual decrease in V, Ni, Cr, and Mn that correlates with the transition from early, amphibole-biotite-magnetite dominant alteration to late, chlorite-quartz-hematite-dominated alteration assemblages.
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The Ningwu and Luzong volcanic fields of the Middle and Lower Yangtze River Metallogenic Belt, eastern China, host >40 known IOA deposits with a total …
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There are two major types of deposit. The first, and by far the most important, is banded iron formations ( BIFs ), so called because they are finely layered alternations of cherty silica and an iron mineral, generally hematite, magnetite, or siderite. BIFs can be divided into two kinds. The first, and quantitatively most important, is found in ...
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Geochemistry of hematite veins in IOA-IOCG deposits of SE Missouri, USA: Relation to felsic magmatism and caldera lakes. August 31, 2019. The …
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Results of preliminary investigations into the geological setting, petrography and geochemistry of BIF-hosted high-grade hematite iron ore deposits in South Africa, …
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Magnetite (Fe 3 O 4) is the primary CP found in deposits because of the reducing conditions in secondary circuit [6]. Under certain exceptional less reducing conditions (e.g. air ingress and inadequate hydrazine content), it is possible that part of the magnetite goes through oxidation and transforms into ferric oxides, in particular …
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Hematite is the abundant form of iron oxide, natural red pigment, and an integral part of the largest iron ore deposits on Earth. Highly aesthetic crystals and shiny botryoidal hematite aggregates are …
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We conclude it is plausible that the friable layered equatorial deposits could have come from explosive eruptions of distal volcanoes. Hematite may have formed as Fe-rich deposits that were oxidized …
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