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The presence of iron-solubilising bacteria in the weathered, naturally exposed part of a large sulfide ore deposit (gossan) in the High Arctic (eastern North Greenland, 83°N) was demonstrated. Microscopic examination of ore material and enrichment cultures in minimal medium containing FeS 2 or Fe 2+ as sole inorganic electron donors revealed ...
25 ABSTRACT 26 Porosity plays a key role in the formation and alteration of sulfide ore minerals, yet our knowledge 27 of the nature and formation of the residual pores is very limited. Herein, we report the application of 28 ultra small angle neutron scattering and small angle neutron scattering (USANS/SANS) to assess 29 the porosity in five natural sulfide minerals (violarite, marcasite ...
This form of pollution may arise from mine wastes (acid mine drainage) or sulfide-containing natural rocks (acid rock drainage). The literature on sulfide minerals is extensive, with a number of overview textbooks and monographs. Comprehensive reviews can be found in Ribbe (1974), Vaughan and Craig (1978), and, most recently, in Vaughan (2006).
In natural magmatic sulfide ore systems, PGEs are collected by immiscible sulfide droplets that segregate from a silicate magma. The studies reviewed here suggest that, during fractionation and cooling of the sulfide liquid, Rh, Ir, Os, Ru and Ni may partition effectively into the earliest crystallising phase, monosulfide solid solution, which ...
Within gold ores, the element occurs in nature chiefly as native gold, which is by far the most common gold bearing mineral. In various gold ores, the native gold commonly occurs as tiny particles contained within sulfide minerals such as pyrite. Iron pyrite is an exceedingly common associate with gold, but it also serves as a reducing agent.
Hydrogen sulfide can easily be made from low-grade copper matte, or from matte made specially for the purpose. It might well be used as a precipitant for copper, either from a clear solution or in a pulp, following solution by acid, and preceding flotation, either of the precipitated sulfides alone or together with the natural sulfides of the ore.
Gold ore is considered free-milling when over 90% of the gold can be recovered by a conventional gravity-cyanidation process with low reagent consumptions at a grind size of 80% passing 75 µm. Some examples of free-milling gold ores include quartz-veined deposits and oxidized ores. Sulfide …
For copper sulfide ore, ... ore: A naturally occurring mineral containing valuable elements (often metals) which can be extracted from the surrounding mineral at a profit. ore reserve: A concentration or deposit of minerals in the earth's crust which is valuable and can be mined at a profit.
Wisconsin legislators pass bill to repeal a Prove-it-First law, tacitly confirm that all sulfide-ore copper mines pollute. On Tuesday November 7, Wisconsin lawmakers eager to promote sulfide-ore copper mining passed and sent a bill to repeal that state's "Prove it First" sulfide mining moratorium law to Governor Walker's desk. The Prove-it-First law was passed in 1998 and obligates any ...
sulfide minerals and descending, acidic meteoric waters; these processes take place at or near the ground surface in subaerial environments (Guilbert and Park, 1986). In VMS deposits, copper and other metals are mobilized from primary massive sulfide ore and reprecipitated at …
These ores are naturally resistant to recovery by standard cyanidation and carbon adsorption processes. These refractory ores require pre-treatment in order for cyanidation to be effective in recovery of the gold. A refractory ore generally contains sulfide minerals, organic carbon, or both.
This form of pollution may arise from mine wastes (acid mine drainage) or sulfide-containing natural rocks (acid rock drainage). The literature on sulfide minerals is extensive, with a number of overview textbooks and monographs. Comprehensive …
Sulfides of many important metallic elements are naturally occurring minerals. For example, pyrite, which is also called fool's gold owing to its brassy yellow colour, is a sulfide of iron with the formula FeS 2. Pyrite is a major source of iron and is one of the most abundant of the sulfur minerals.
The presence of iron‐solubilising bacteria in the weathered, naturally exposed part of a large sulfide ore deposit (gossan) in the High Arctic (eastern North Greenland, 83°N) was demonstrated. Microscopic examination of ore material and enrichment cultures in minimal medium containing FeS 2 or Fe 2+ as sole inorganic electron donors revealed ...
Sulfide-Ore Copper Mining or (not and) a Sustainable Boundary Waters Economy iv ... natural resource stewardship, environmental quality, and human well-being for more than 25 years. He was a staff economist first at the White House Council on Environmental Quality during the first . the
Copper sulfide ores. The method used to separate copper in copper sulfide ores depends on the concentration of the copper. Higher concentrated ores …
The smelter for sulfide ores produces sulfur dioxide gas. This is scrubbed from the flue gases to make sulfuric acid for leaching copper from oxide ores. Scrubbing sulfur dioxide also protects the environment. For example: FeO(s) + SiO 2 (s)→ FeO.SiO 2 (slag) This is …
Magmatic sulfide ore deposits are products of natural smelting: concentration of immiscible sulfide liquid ('matte'), enriched in chalcophile elements, derived from silicate magmas ('slags'). Sulfide ore deposits occupy a spectrum from accumulated pools of …
magmatic sulfide deposits where the principal ore mineral is pentlandite [(Ni,Fe) 9 S 8]. The ionic radius of divalent nickel is close to that of divalent iron and magnesium, allowing the three elements to substitute for one another in the crystal lattices of some silicates and oxides.
Table 2 shows the main types of ore deposits that contain significant amounts of sulfide minerals, their major ore minerals, the metals extracted from them, and some specific examples (see Cox and Singer 1987; Craig and Vaughan 1990, 1994). Pyrite is abundant in nearly all of these deposits.
The principle use of sulfur isotopes has been to understand the formation of sulfide ore deposits, which may originate in either sedimentary or igneous environments. The sulfur associated with sedimentary processes generally reflects the composition of biogenic sulfide produced by bacteria reduction of marine sulfate, and has negative d 34 S ...
Metallic sulfide mining (aka hard rock mining) is the practice of extracting metals such as nickel, gold and copper from a sulfide-rich ore body. Sulfides are a geologic byproduct of mining in this area, and by exposing sulfides to the air and water in our atmosphere, sulfuric acid can be created — threatening to poison the nearby water ...
Natural ores of several metals such as Ni, Zn, Fe, As, and Cu generally exist in metal sulfide form. Unlike oxidic minerals, metals sulfide is insoluble in normal and weak acidic conditions. Role of ferrous- and/or sulfur-oxidizing microorganisms have been studied widely in metal extraction from metals sulfide [ 94 ].
Magmatic sulfide ore deposits are products of natural smelting: concentration of immiscible sulfide liquid ('matte'), enriched in chalcophile elements, derived from silicate magmas ('slags'). Sulfide ore deposits occupy a spectrum from accumulated pools of matte within small igneous intrusions or lava flows, mined primarily for Ni and ...
The most common sulfide crystalling in this manner is galena (PbS), the ore mineral of lead. A type of packing that involves two sulfide ions in each of the octahedral positions in the sodium chloride structure is the pyrite structure. This is a high-symmetry structure characteristic of the iron sulfide…
The Sulfide Class minerals comprise an economically important class of minerals. Most major ores of important metals such as copper, lead and silver are sulfides. Strong generalities exist in this class. The majority of sulfides are metallic, opaque, generally sectile, soft to average in hardness and they have high densities, black or dark-colored streaks, and an igneous origin.
Lead is found naturally as a sulfide ore containing small amounts of copper, iron, zinc, precious metals, and other trace elements. The lead in this ore, typically after being concentrated at or near the mine (see Section 12.18), is processed into metallurgical lead at 4 facilities in the U. S.
Answer (1 of 5): The concentrated ore ( received after crushing and floating) is roasted in a furnace in the presence of a current of air. Sulphur is oxidized to SO2 and impurities of arsenous and antimony are removed as volatile oxides. The following reaction takes place. 2CuFeS2 + O2 —- Cu2S ...
Talc is one of the most problematic hydrophobic gangue minerals that occur in sulfide ores such as molybdenite and Pt-bearing nickel sulfide ores. Owing to its strong natural hydrophobicity, talc ...
The most common sulfide crystalling in this manner is galena (PbS), the ore mineral of lead. A type of packing that involves two sulfide ions in each of the octahedral positions in the sodium chloride structure is the pyrite structure. This is a high-symmetry structure characteristic of the iron sulfide…
Metalloids, most significantly arsenic, can also be present at highly elevated concentrations in sulfide ore leach liquors; arsenopyrite (FeAsS) and realgar (As 4 S 4) are two other relatively common sulfide minerals. Waters percolating through fissures in worked-out underground mines, as well as those draining stockpiled mine waste rock dumps ...
In addition to tailings dam failures and pipeline leaks, sulfide-ore copper mines can pollute through seepage from underground pits and surface waste rock and sulfide-bearing ore. These pollution vectors are hard to detect and difficult to fix. By exposing sulfides minerals in the pit walls to oxygen and water, they are able to produce acid ...
An economical and environmentally friendly beneficiation process is of great practical significance for the mining industry to achieve green and sustainable development. This study aims to optimize the traditional flotation process of Mo−Bi sulfide ore by using the difference in natural floatability of minerals for cleaner production. Single-mineral flotation tests demonstrate that the ...
This study aims to optimize the traditional flotation process of Mo–Bi sulfide ore by using the difference in natural floatability of minerals for cleaner production. Single-mineral flotation tests demonstrate that the natural floatability of the sulfide minerals investigated decreased in the following order: molybdenite > bismuthinite > pyrite.
separating sulfide minerals from silica gangue (and from other sulfide minerals); separating ... Problem: A copper ore initially contains 2.09% Cu. After carrying out a froth flotation ... Particles can either be naturally hydrophobic, or the hydrophobicity can be induced by chemical
Cinnabar, mercury sulfide (HgS), is the principal ore of mercury. (more below) Cinnabar is very dense, 8.1 times as dense as water, has a distinctive red streak and has hardness 2.5, barely scratchable by the fingernail. There are very few minerals that might be confused with cinnabar, but realgar is softer and cuprite is harder.
Some sulphide minerals are economically essential as metal ores. The sulphide class also includes the selenides, tellurides, the antimonides. Sulfide minerals are the inorganic compound. Following are the sulfide ores of the metals: Sulfide ore of silver is Argentite $(A{{g}_{2}}S)$. It is …
Typically, the sulfide body is a concordant lens underlain by a discordant stockwork or stringer zone with vein-type sulfide mineralization (fig. 7–1) (Galley and others, 2007). Based on the shape and depth of the ore body, the sulfide content in the ore produces significant geophysical signatures.