Iron-nickel Sulfide Research Articles

Mineralogy and texture of Fe-Ni sulfides in CI1 chondrites: Clues to the extent of aqueous alteration on the CI1 parent body

To better understand the role of aqueous alteration on the CI1 parent body, we have analyzed the texture, composition and mineral associations of iron nickel sulfides in four of the five known CI1 chondrites. The most commonly-occurring sulfide present in the CI1 chondrites is the iron-deficient Fe,Ni sulfide pyrrhotite ([Fe,Ni] 1−xS), that has a composition close to that of stoichiometric troilite (FeS). Three of the CI1s (Alais, Ivuna and Tonk) also contain pentlandite ([Fe,Ni] 9S 8), although pentlandite is a rare phase in Ivuna. Cubanite (CuFe 2S 3) was found in both Alais and Ivuna in this study, although it has also been reported in Orgueil ( MacDougall and Kerridge, 1977). The pyrrhotite grains in all four chondrites form hexagonal, rectangular or irregular shapes, and show no evidence of Ni or Co zoning. The pyrrhotite grains in Orgueil and Ivuna are, in general, smaller, and show more “corrosions,” or “embayments,” than those in Alais or Tonk. We suggest that the precursor sulfide present in the CI1 chondrites was troilite which, during brecciation and oxidation on the parent body at a temperature of 100°C or less, converted the troilite to magnetite and pyrrhotite with pentlandite inclusions. Subsequently, continued alteration on the parent body removed pentlandite—partially from Alais, Tonk and Ivuna, completely from Orgueil—leaving behind pyrrhotite with spaces (“corrosions”) where the pentlandite had been. Ni derived from the pentlandite was incorporated into ferrihydrite, onto the surface of which the Ni,Na sulfate Ni-bloedite formed. Based on the size and abundant “corrosions” within pyrrhotite grains, combined with observations from other authors, we conclude that Orgueil and Ivuna have undergone a greater degree of alteration than Alais and Tonk. Further work is needed to assess the conditions under which pentlandite would be dissolved preferentially to pyrrhotite, as the study of terrestrial literature indicates that the latter mineral is preferentially removed.

Mineralogy of carbonaceous chondritic microclasts in howardites: identification of C2 fossil micrometeorites

Seventy-one carbonaceous chondritic microclasts of average size 150 μm have been found in three howardites (Yamato-793497, Jodzie, Kapoeta). All carbonaceous chondritic microclasts are made of a fine-grained phyllosilicate-rich matrix supporting a variety of minerals such as olivine, pyroxene, spinel, iron oxides, iron–nickel sulfides, and calcium carbonates. Such a mineralogy is typical of chondritic C2 matter. Half of the carbonaceous chondritic microclasts are tochilinite-rich, and have been tentatively called CM2 microclasts. The other half are magnetite-rich, and have been tentatively called CR2 microclasts. The absence of a correlation between the CM2/CR2 ratio in carbonaceous chondritic microclasts and in numerous millimeter-sized clasts found in the same sections argues for carbonaceous chondritic microclasts being true micrometeorites rather than fragments of larger objects. Dynamical simulations show that it is possible for asteroidal dust to encounter Vesta (the howardite’s putative parent-asteroid) at velocity low enough (<1 km.s −1) to prevent fragmentation. Because the micrometeorite flux in the inner Solar System has been decreasing with time, we argue that carbonaceous chondritic microclasts have been trapped in Vesta’s regolith early in the history of the Solar System and are fossil micrometeorites. Because both microclasts and clasts found in howardites are related to C2 chondritic matter, we propose that C2 matter represents the bulk, or at least a significant fraction of the primordial howardite parent-asteroid. Considering the abundance of C2 matter among fossil micrometeorites, we speculate that the C2 fossil micrometorites are the so far unidentified agent of the late chondritic veneer that endowed the Earth’s mantle with an excess of siderophile elements relative to the contents predicted by the core–mantle separation models. The discovery that C2 fossil micrometeorites are similar to C2 modern Antarctic micrometeorites supports recent models proposing a micrometeoritic origin for the Earth’s oceans and volatile species.

Hydromagmatic amphibole in komatiitic, tholeiitic and ferropicritic units, Abitibi greenstone belt, Ontario and Qu�bec: evidence for Archaean wet basic and ultrabasic melts

¶Detailed petrographic, electron microprobe and ion probe studies of Archaean hydromagmatic amphiboles from the Abitibi greenstone belt, Canada, yield new insights into the origin of Al-undepleted komatiitic and Al-depleted tholeiitic and ferropicritic melts. The amphiboles are present in peridotite layers and basal chill zones of thick differentiated basic and ultrabasic sills and flows, and are titanian pargasite–hastingsite in composition. They can be grouped into two petrographic types: (1) amphibole in the groundmass; and (2) amphibole-bearing melt inclusions. The groundmass amphiboles are oikocrysts, rims and interstitial grains, present in minor to major amounts. The oikocrysts host cumulus olivines (Fo83–84) that are rounded in shape, embayed, and smaller in size. The amphibole-bearing melt inclusions are hosted in cumulus olivines (Fo83–84 in komatiitic rocks and Fo79 in tholeiitic rocks), spherical to ovoid in shape, 50–500 µm in size, and dominated modally by amphibole. The melt inclusions also contain euhedral chromite and aluminous spinel and micrometric clinopyroxene and glass, and sub-micrometric iron–nickel sulphide, chloro-apatite and ilmenite. In-situ ion probe analyses indicate the amphibole is: (1) enriched in Nb, LREE and Zr and depleted in Sr and HREE relative to primitive mantle; (2) contains up to 1–3 wt% H2O; and (3) overall displays δD values from 50‰ to −140‰, including many values in the accepted magmatic range of −60‰ to −90‰.

The adaptation of Thiobacillus ferrooxidans for the treatment of nickel–iron sulphide concentrates

Thiobacillus ferrooxidans was successfully adapted to copper–nickel–iron and pyrrhotite concentrates. Bacterial leaching in a culture medium at initial pH 2 resulted in increased solubilisation of the metals for both concentrates. Two strains, designated NatTf and ConTf, both showed similar overall % metal solubilisation in the order Ni>Fe>Cu. Extraction corresponded to the growth phase but the leaching rate for ConTf exceeded that for NatTf during the exponential phase. However, during the stationary phase the rate for ConTf was much lower than for NatTf. X-ray diffraction indicated the early production of elemental sulphur and reduced iron compounds in leach residues from ConTf limiting the rate. No evidence was found for direct attachment leaching. The order of oxidation of the minerals was pyrrhotite>sphalerite>chalcopyrite>violarite>pentlandite>pyrite because oxidation of Fe(II) to Fe(III) led to galvanic interactions where Fe(III) oxidises minerals with lower mixed-potential. Leaching models indicated a mixed kinetic regime with initial film diffusion control and subsequent shrinking-core product layer diffusion control.

Solubility of carbon in sulfide melts of the system Fe-Ni-S

The solubility of carbon in iron-nickel sulfide melts at 1673 K was studied in the entire range of compositions of the Fe-FeS-Ni3S2-Ni tetragon. The boundaries of the stratification area were determined in this system upon its being saturated with carbon. Lines of carbon isosolubility are plotted in the tetragon field outside the stratification area.

Spectroscopic Characterization of Ethyl Xanthate Oxidation Products and Analysis by Ion Interaction Chromatography

An ion interaction chromatographic separation method, coupled with UV spectroscopic detection, has been developed for the analysis of ethyl xanthate (O-ethyl dithiocarbonate) and its oxidative decomposition products in mineral flotation systems. The effects of the ion-pairing agent (tetrabutylammonium ion), pH modifier (phosphoric acid), and organic modifier (acetonitrile) in the eluant upon the retention characteristics of the ethyl xanthate oxidation products have been determined. The optimized separation procedure has been successfully applied to the analysis of ethyl xanthate and its oxidation products in a nickel-iron sulfide mineral suspension containing a number of other anionic species, including cyanide complexes of nickel and iron, as well as sulfur-oxy anions. The ethyl xanthate oxidation products investigated in this study have been isolated as pure compounds and characterized by UV-visible, FT-IR, and NMR spectroscopies. The UV-visible and FT-IR spectroscopic properties of these species are discussed in terms of the chemical modifications of the thiocarbonate group.

The oxidation of sulphide minerals

The literature associated with the thermal behaviour of mineral sulphides has been selectively and critically reviewed. Particular attention has been paid to: • the importance of characterising the starting material, as well as intermediate products • the effect of experimental variables on the thermal analysis results The various reactions that sulphides can undergo in inert and oxidising atmospheres are presented. Under mild oxidising conditions, such as an air atmosphere and heating rates of 10–20°C min−1, the oxidation occurs as a sequence of reactions usually controlled by oxygen diffusion, although in some situations decomposition of the sulphide with evolution of sulphur can occur. Besides the formation of oxides and sulphates, and the subsequent decomposition of the latter, solid-solid reactions can occur between sulphates and unreacted sulphides. In ternary systems, such as the iron-nickel sulphides, considerable ion diffusion can take place. Under more vigorous oxidising conditions, such as an oxygen atmosphere with a heating rate in excess of 40°C min−1, some sulphides can be ignited. Under these conditions the relative ignition temperatures of sulphides can be measured, and the effects of variables such as particle size and stoichiometry on the ignition temperature examined. The oxidation of pyrite is presented as a case study of the effects of experimental variables on the results of thermal analysis. The application of the results of studies to the industrial processing of sulphides of economic importance has been discussed.

Iron and iron-nickel sulfides in chondritic interplanetary dust particles

We report the results of a study of iron and iron-nickel sulfides in chondritic anhydrous and hydrated interplanetary dust particles (IDPs). The IDPs were characterized using chemical and mineralogical techniques including energy dispersive X-ray analyses and transmission electron microscopy. It is widely believed that the first sulfur-containing mineral to form in the early solar nebula should have been stoichiometric FeS (troilite), and that pyrrhotite is of secondary origin. All examined interplanetary dust particles, both anhydrous and hydrous types, contain more pyrrhotite than troilite, suggesting that the former was a common, possibly predominant nebular condensate phase. Pyrrhotite could form from sulfidation of troilite, after the latter had exfoliated from substrate metal grains. In contrast to anhydrous IDPs, hydrated ones contain Ni-rich sulfides, including pentlandite, which are probably of secondary origin.

Nickel sulfide, iron-nickel sulfide and iron sulfide precipitation by a newly isolated Desulfotomaculum species and its relation to nickel resistance

A Desulfotomaculum sp. (DF-1) isolated from a sulfate reduction bioremediation pilot plant in Chengdu (P.R.C.) was resistant to 360 (6.1 mM), 450 (7.7 mM), and 550 ppm (9.4 mM) Ni(II) in the presence of 0, 100 (1.8 mM), and 200 ppm (3.6 mM) Fe(II), respectively. When cultured in the presence of Ni (II) with or without Fe, DF-1 produced a dark-brown, soluble product. Only small amounts of Ni and or Fe were precipitated at the cell surface when cells were subjected to 100 ppm concentrations of the metals. However, in the presence of Fe(II) only, large amounts of FeS (70% of the Fe) were precipitated at the bacterial cell surface and extracellularly. The increase of Ni in the growth medium was inversely related to the concentration of Fe precipitated as a sulfide. This coincided with the formation of dark-brown, soluble Ni-proteins, consisting of a range of polypeptides from approx. 70–120 kDa, which inhibited NiS formation and promoted Fe-complexation. These autolysis-inducible proteins and cell wall autolysis by-products bound Ni, and are thought to confer Ni-resistance in DF-1. Harsh treatments, such as acidification of culture supernatants from Ni-grown DF-1, destabilized the Ni-organic complexes, and resulted in the precipitation of an amorphous Ni-rich material.

Nickel sulfide, iron-nickel sulfide and iron sulfide precipitation by a newly isolated Desulfotomaculum species and its relation to nickel resistance

A Desulfotomaculum sp. (DF-1) isolated from a sulfate reduction bioremediation pilot plant in Chengdu (P.R.C.) was resistant to 360 (6.1 mM), 450 (7.7 mM), and 550 ppm (9.4 mM) Ni(II) in the presence of 0, 100 (1.8 mM), and 200 ppm (3.6 mM) Fe(II), respectively. When cultured in the presence of Ni (II) with or without Fe, DF-1 produced a dark-brown, soluble product. Only small amounts of Ni and or Fe were precipitated at the cell surface when cells were subjected to 100 ppm concentrations of the metals. However, in the presence of Fe(II) only, large amounts of FeS (70% of the Fe) were precipitated at the bacterial cell surface and extracellularly. The increase of Ni in the growth medium was inversely related to the concentration of Fe precipitated as a sulfide. This coincided with the formation of dark-brown, soluble Ni-proteins, consisting of a range of polypeptides from approx. 70–120 kDa, which inhibited NiS formation and promoted Fe-complexation. These autolysis-inducible proteins and cell wall autolysis by-products bound Ni, and are thought to confer Ni-resistance in DF-1. Harsh treatments, such as acidification of culture supernatants from Ni-grown DF-1, destabilized the Ni-organic complexes, and resulted in the precipitation of an amorphous Ni-rich material.

The effect of chlorine on the high temperature corrosion of SiO2-coated Incoloy 800H

The effect of chlorine in coal gasification atmospheres was investigated on the high temperature corrosion of Incoloy 800H coated with SO2. The experiments were performed in a representative gas mixture between 450 and 750 OC. The weight gain in this environment was significantly decreased with coating thicknesses to about 1.4 pm. Larger thicknesses led to an increased corrosion attack. The coating contained small cracks filled with iron-nickel sulphides. Probably, pre-existing cracks in the SOn-coating due to internal stresses, were responsible for this behaviour of the coating. With increasing temperature or pa,, the corrosion rate increased. The mechanism of the chlorine-induced corrosion is unclear as yet.

Étude métallographique des différentes associations minérales et caractérisation chimique des minéraux uranifères du gisement de Cigar Lake (Saskatchewan, Canada)

The Cigar Lake deposit, discovered in 1981, represents one of the richest uranium occurrences known in the province of Saskatchewan. The eastern margin of the Athabasca Basin can be considered as one of the richest uraniferous provinces in the Western World.Being located at the unconformity between the Aphebian metasediments and the Helikian sandstone cover, this deposit is classified in the group of deposits spatially related to the Proterozoic unconformity. The study of this deposit, exceptional in its dimensions, grade, and tonnage, was made possible through a series of 170 boreholes drilled to delineate the whole orebody to a depth of 440 m.The metallographic study of the mineralizations in the main orebody, hosted in the basement, and the so-called "perched" mineralization in the cover rocks, led to the definition of three major mineralizing stages, which contributed in varying degrees to ore deposition.A major stage is characterized by the association of U–Ni–Co–As–S ± Mo–Bi–Cu–Zn–Pb and reflects the polyphased nature of this hydrothermal stage. This early deposition of the uraniferous phase (massive, botryoidal, and euhedral uraninite) was followed, on one hand, by a phase precipitating nickel–cobalt and Feron arsenides and sulfoarsenides, and on the other hand, by a phase exclusively of sulphides. The age of emplacement of this stage is 1341 Ma, and it corresponds to the very important metallogenic period in the Athabasca during which the main economic ore occurrences "related to unconformities" were emplaced.The second stage appears only in the metamorphic units of the Aphebian basement. It is represented by an uraninite–sulphide paragenesis, the uraninite being characterized principally by the presence of thorium and, as well, a lead content lower than that in the uranous oxides stage.The third mineralizing stage affects the basement rocks, the main orebody, and the cover rocks with their perched mineralization. It is a simple pitchblende – iron or iron–nickel sulphide and (or) hematite paragenesis with an age of emplacement of 323 Ma. This type of mineralization is identical to that shown in a certain number of occurrences in the Athabasca Plateau and it is considered to be related to the Hercynian orogeny.The first and third of these three mineralizing stages fit perfectly in the metallogenic model for this part of the Canadian Shield. A comparison of these stages with the main mineralizing stages defined in the Carswell Dome structure and with some occurrences in eastern Athabasca was carried out in order to define a model of the metallogenic evolution of northern Saskatchewan. [Journal Translation]

Magnetic iron-nickel sulphides in the Pliocene and Pleistocene marine marls from the Vrica section (Calabria, Italy)

The rock magnetic properties of the late Pliocene and early Pleistocene open-marine marls from the Vrica section in Calabria (Italy) point to magnetic sulphide as the main magnetic mineral and remanence carrier. The maximum blocking temperatures, however, are between 340 and 360°C, which is too high for stoichiometric monoclinic pyrrhotite. Magnetic concentrates of the sediment are rich in iron sulphide grains and iron-nickel sulphide grains. Microprobe observations show that most of the grains are of the order of 1 μm in size and attached to iron-bearing clay flakes. Microprobe analyses of the sulphides yield a large range of compositions, ranging from pyrite through greigite-pyrrhotite to sulphur-deficient monosulphides, and with Ni contents varying from zero to a few atom percent in the pyrite grains and from zero to as much as 35 atm% in the monosulphides. The high Ni content of many of the grains is extraordinary and has not been reported before in marine sediments. Most of the compositions cannot be directly connected with a known mineral phase. The marine depositional environment of the marls imposes an authigenic origin for the sulphides, and this is supported by several observations. The great number of sulphide grains in the magnetic concentrates suggests that at least one of the sulphide compositions must have a ferrimagnetic structure, possibly the sulphides with a metal to sulphur ratio close to that of monoclinic pyrrhotite, and between 25 and 35% of the Fe replaced by Ni. The Ni substitution could possibly be the cause of the high blocking temperatures.

Microbiologically Induced Corrosion of UNS N04400 in Seawater

Abstract Laboratory and field immersion tests were conducted on UNS N04400 (Mone 400) to assess its susceptibility toward microbial attack in Arabian Gulf seawater. Specimens were exposed to chlorinated and nonchlorinated seawater for periods up to four months. Other tests included exposure of UNS N04400 to a prepared culture of sulfate-reducing bacteria (SRB). The results indicated that SRB attack initiated beneath a black sulfide-rich deposit, overlaid by a green chloride-rich deposit, and a beige-colored calcareous scale was on all specimen surfaces after long exposure periods. The black layer was comprised mainly of one or more iron-nickel sulfides (Fe, Ni)xSy and nickel sulfide (Ni3S4), whereas the green layer was essentially CuCl2 × 3Cu(OH)2 with a low concentration of NiCl2. These deposits were in the form of nodules scattered on the surface, and, when removed, circular attacked areas or cavities were revealed. Scanning electron microscopy examinations of these areas indicated severe intergranular ...

One-step recovery of nickel by an electrohydrometallurgical process

The one-step electroleaching-electrowinning of nickel from violarite and pentlandite iron-nickel sulphide concentrates has been demonstrated using an electrochemical cell fitted with a cation exchange membrane. Oxidants were electrogenerated in the anode compartment, which contained a slurry of the concentrate, and dissolved nickel electrowon in the cathode compartment. Nickel powder of greater than 99% purity with an iron content of 0.2% was obtained.

The measurement of ignition temperatures and extents of reaction on iron and iron-nickel sulfides

Four mineral sulfides typically found in the feed stock of a commercial nickel flash smelter, namely pyrite, violarite, pyrrhotite and pentlandite, were isolated from a primary and a supergene ore sample using magnetic separation. Relatively pure samples of pyrite, pyrrhotite and pentlandite were obtained, but violarite could only be upgraded to a 40–50% mixture with pyrite. These samples were characterized by chemical analysis, optical microscopy, Electron Probe Microanalysis (EPMA), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Thermogravimetry-Differential Thermal Analysis (TG-DTA). Each sample was split into four fractions of particle size 20–45Μm, 45–75Μm, 75–90Μm and 90–125Μm. Ignition temperatures and extents of reaction were determined using an isothermal thermogravimeter, and the products were characterized by electron microscopy. Pyrite and violarite were found to be the most reactive to ignition, followed by pyrrhotite, with pentlandite being the least reactive. This order contradicts the results of other studies and various possible causes for this are discussed. The observed trend of increasing ignition temperature with increasing particle size was in agreement with previously published reports. The extent of reaction of each mineral was measured at increasing furnace preheat temperatures. These plots were correlated with the morphology of the products formed at the ignition temperature.

Geochemistry of the Île Cadieux monticellite alnöite, Quebec, Canada

The Île Cadieux alnöite, a small Cretaceous intrusion, is a member of the Monteregian Hills Petrographic Province. Mineral chemistry was determined for olivine, spinel, clinopyroxene, melilite, and a potassium–iron–nickel sulphide akin to djerfisherite. Whole rocks were analysed for major elements and 24 trace elements (including rare-earth elements). The Île Cadieux alnöitic rocks have greater MgO/Al2O3 ratios than most alnöites but are otherwise similar to typical alnöites with respect to major and trace elements. Comparison of spinel and whole-rock chemical compositions from the Île Cadieux and Île Bizard (located 15 km to the northeast) alnöitic intrusions suggests that these magmas were generated under different physicochemical conditions of melting, or alternatively that they are fractions of a single magma which crystallized under different conditions.

ChemInform Abstract: REACTIONS OF IRON SULFIDE (FES2), COBALT SULFIDE (COS2), AND NICKEL SULFIDE (NIS2) ELECTRODES IN MOLTEN LITHIUM CHLORIDE‐POTASSIUM CHLORIDE ELECTROLYTES

Chemischer InformationsdienstVolume 14, Issue 21 Physical Inorganic Chemistry ChemInform Abstract: REACTIONS OF IRON SULFIDE (FES2), COBALT SULFIDE (COS2), AND NICKEL SULFIDE (NIS2) ELECTRODES IN MOLTEN LITHIUM CHLORIDE-POTASSIUM CHLORIDE ELECTROLYTES S. K. PRETO, S. K. PRETOSearch for more papers by this authorZ. TOMCZUK, Z. TOMCZUKSearch for more papers by this authorS. VON WINBUSH, S. VON WINBUSHSearch for more papers by this authorM. F. ROCHE, M. F. ROCHESearch for more papers by this author S. K. PRETO, S. K. PRETOSearch for more papers by this authorZ. TOMCZUK, Z. TOMCZUKSearch for more papers by this authorS. VON WINBUSH, S. VON WINBUSHSearch for more papers by this authorM. F. ROCHE, M. F. ROCHESearch for more papers by this author First published: May 24, 1983 https://doi.org/10.1002/chin.198321017Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume14, Issue21May 24, 1983 RelatedInformation

Deep-seated iron ores from banded-iron formation

Very large iron ore deposits have formed in many parts of the world, evidently by the supergene alteration of Precambrian banded-iron formation (BIF). Some of these deposits extend to great depths, ranging to 2,400 m at Krivoyrog1, beyond the likely reach of oxygenated water. We propose here, on the basis of studies in the Hamersley Ranges, Western Australia, a mechanism for deep-seated ore formation in which electronic conduction through the magnetite layers in BIF connects a cathodic region near the surface, where oxygen is reduced, to an anode at depth, where iron (II) from magnetite, carbonates and silicates is oxidized and precipitated as iron (III) hydroxyoxides. The electrical circuit is completed by ionic conduction through groundwaters. The model is based broadly on a mechanism suggested by Sato and Mooney2 to explain self-potentials associted with sulphide ore bodies. It is based more specifically on a model demonstrated by Thornber3 for the weathering of massive nickel–iron sulphide deposits at Kambalda, Western Australia, but with substantial differecnes in the physical situation and the reactions at depth.

Iron-nickel sulfides in the Murchison meteorite and their relationship to phase Q1

Pentlandite from the Murchison meteorite survives HF-HCl attack and dissolves in HNO 3 at room temperature, thus satisfying the operational definition of phase Q1, the proposed major carrier of carbonaceous chondrite fission xenon. However, identification of pentlandite with that phase is problematical in view of apparently differing thermal stabilities.