Pyrite (aka "fool's gold" or "iron pyrite") is a metallic looking material with numerous applications. Its chemical formula is FeS 2, meaning that it is a compound made up of iron (Fe) and Sulphur (S).
Download scientific diagram | (a, b) Disseminated pyrite and magnetite grains distributed along linear features in fractures and pores. (c, d) Framboidal clusters of pyrite and magnetite in source ...
Pyrite and magnetite are some of the most common accessory minerals in many ore deposits. They form over a large spectrum of geological and hydrothermal conditions and incorporate various trace elements into their structure (e.g., Carew, 2004; Reich et al., 2005; Rusk et al., 2009; Large et al., 2009; Dupuis and Beaudoin, 2011; Ciobanu et al., 2012).
The chemical compositions of magnetite and pyrite can be used to determine source of ore-forming materials (Dare et al., 2014, Mukherjee and Large, 2017, Ding et al., 2018, Wang et al., 2017, Chen et al., 2018), the nature and evolution of the ore-forming fluid (Chen et al., 2015, Hu et al., 2017), and the mobility of elements during late-stage ...
A 'new' type of arsenian pyrite was formed during experimental replacement of magnetite under hydrothermal conditions (T = 125 and 220 °C; Psat) and in the presence of S(-II) and various As-containing species. The amount of As in pyrite depended on the As-source, with sources containing cationic As (As(II), As(III) and As(V)) resulting in considerably higher …
The chlorinated benzene 1,4-DCB is chemically stable (Table S1) and is the byproduct of producing long-chain aromatic compounds, such as alpha-hexachlorobenzene (γ-HCH).Liu et al. (2003) reported that 1,4-DCB was a dominant byproduct of γ-HCH transformation via reductive elimination and dehydrochlorination by mackinawite (FeS). Reduction of γ-HCH …
Request PDF | Sulfidation of nano-magnetite to pyrite: Implications for interpreting paleoenvironmental proxies and biosignature records in hydrothermal sulfide deposits | Nano-magnetite is a ...
DOI: 10.1016/J.GCA.2010.06.035 Corpus ID: 129327515; An experimental study of the mechanism of the replacement of magnetite by pyrite up to 300 °C @article{Qian2010AnES, title={An experimental study of the mechanism of the replacement of magnetite by pyrite up to 300 °C}, author={Gujie Qian and Jo{"e}l Brugger and William Skinner and Guorong Chen and Allan …
Whereas dissolution of magnetite associated with the pyritization of organic-rich sediments has been documented by several workers (e.g., Canfield and Berner, 1987), instances of the …
Ferric complexes of oxalate, salicylate and acetylacetonate resulted in pyrite dissolution and magnetite formation. The activity of strongly reducing ligands (e.g., catechol) or unsaturated Fe(III)-exchange capacity (particularly in experiments with bentonite or with solutions of uncomplexed ligands) can result in an effective reduction of ferric iron concentration and …
Pyrite, with the chemical formula FeS 2, is a ubiquitous mineral in coal and is a harmful colour-stained impurity in kaolinite-rich coal gangue, which is widely used as a raw material to produce calcined kaolin in many factories.Transformation of pyrite to various phases under calcination may influence and even decide ways of comprehensively utilizing of coal …
The pyrite stability field increases from 300 to 100°C at lower Eh conditions. The gouge appears to have formed under anoxic conditions based on microbial observations at 1,000 m depth in TCDP core Hole A [Wang et al., …
Mineralisation occurs as narrow shear-hosted massive magnetite-pyrite-chalcopyrite-sphalerite ± pyrrhotite forming elongated, flattened pipe-like bodies. ... Moltzen, J. et al. Magnetite trace element characteristics and their use as a proximity indicator to the Avoca Tank Cu-Au prospect, Girilambone copper province, New South Wales, Australia ...
The Gondpipri layered mafic–ultramafic intrusion at the western margin of the Bastar Craton in Central Indiacomprises leucogabbro, gabbronorite, and websterite. The intrusion hosts both magmatic and hydrothermal Ni-platinum group element (PGE)mineralisation. In this study, we use in-situ measured trace element composition of pyrite and magnetite and zircon …
LIMESTONES are an important source of palaeomagnetic data, with magnetite the dominant carrier of the magnetization. Because the magnetite is present in low concentrations, however, it has been directly observed only rarely and in trace amounts in acid-treated separates. Such residues are composed primarily of spheres, the ultimate origin of which has been …
SEM back-scattered electron images of chalcopyrite from different mineralization stages from the quartz monzonite (a-c) and the latite (d-f): (a) chalcopyrite (Cpy) is intergrown with pyrite (Py ...
tions with operating conditions as described by Jiang et al. 16• FIG. 1 Secondary-electron images of magnetite that replaced framboidal pyrite in Onondaga limestone. a, ...
magnetite produces framboid-like pyrite Check for updates Eric Runge 1,2, Muammar Mansor 3, Tsz Ho Chiu 3,JeremiahShuster4,5, Stefan Fischer4, Andreas Kappler 3,6 & Jan-Peter Duda 1,2
An experimental study of the mechanism of the replacement of magnetite by pyrite up to 300 degrees C. Gujie Qian, Joel Brugger, William Skinner, Guorong Chen, ... Chen, G & Pring, A …
of some pyrite framboids (Large et al., 2001; Maclean et al., 2008; Wacey et al., 2015). As biogenic pyrite is difficult to obtain in laboratory culture, the influence of microorganisms on the for-mation of pyrite is barely understood. Most biomineralization experiments using sulfate-reducing bacteria (SRB) reported the formation of mackinawite ...
Geochimica et Cosmochimica Acta, 2013. A 'new' type of arsenian pyrite was formed during experimental replacement of magnetite under hydrothermal conditions (T = 125 and 220°C; P sat ) and in the presence of S(-II) and various As-containing species.
Magnetite-(apatite) rocks are grouped in well-defined clusters that are mostly related to continental magmatic arcs and extensional environments (Table 1).The host rocks are dominantly igneous, calc-alkaline to alkaline, and ranging in composition from felsic to mafic, with a predominance of the former (Table 1).Early studies (Meyer 1988; Hitzman et al. 1992) …
The flat time-resolved signals of laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) imply that trace elements exist mainly in the form of isomorphism in magnetite and pyrite with the exception some incompatible trace elements (e.g., Ca, K and Na in magnetite and Pb, Bi and Ag in pyrite).
Runge, E. A. et al. Sulfidation of nano-magnetite to pyrite: implications for interpreting paleoenvironmental proxies and biosignature records in hydrothermal sulfide deposits. Earth Planet. Sci.
It is known that pyrrhotite may form by prolonged heating pathways, such as reaction of magnetite and pyrite at low-temperature (<200°C) as a result of burial diagenesis and anchimetamorphism (Gillett, 2003). ... This leaves thermal breakdown of pyrite (Bhargava et al., 2009; Lambert et al., 1998) or discharge of hydrothermal fluids ...
All hydrothermal experiments were conducted at ∼pH 21 °C 4 or 3 (Table 1), as our previous study showed that pyrite is the only product under these conditions when magnetite grains ⩾150 μm are used (Qian et al., 2010). Powder XRD analyses confirmed that only (arsenian) pyrite was formed. The reaction of magnetite to arsenian pyrite showed a sharp …
Detailed rock magnetic experiments were conducted on high-purity natural crystalline pyrite and its products of thermal treatments in both argon and air atmospheres. In …
Qian et al. (2009 Qian et al. (, 2010 presented an experimental study on the sulfidation of magnetite to form pyrite/marcasite under hydrothermal conditions (90e300 C, vapor saturated pressures ...
The Yamansu iron deposit, hosted in submarine volcanic rocks, is located in the Aqishan–Yamansu Fe–Cu metallogenic belt of eastern Tianshan, Xinjiang. New pyrite Re–Os and pyroxene diorite intrusion ages and the chemistry of magnetite constrain the origin of the deposit. The Yamansu orebodies display banded or lenticular forms and sharp contacts with marble …
the presence of magnetite-forming microbes (Stolz et al., 1990) and to augment geochemical profiles of early diagenetic processes (Karlin, 1990). Whereas dissolution of magnetite associated with ... The replacement of pyrite by magnetite may be considered to occur, like many other diagenetically and metamorphically formed minerals, by a surface ...
A : cristal de pyrite subautomorphe englobent la magnétite, et début de transformation de la magnétite en hématite. B : monocristal automorphe de pyrite englobe un grain de magnétite. C ...
Even though tempera- Oxidation of pyrite in coal to magnetite: A. N. Thorpe et al. ture equilibrium may not have been completely attained at settings below the final temperature setting, suscepti- bility measurements were made at each setting to detect any sharp changes. When the final temperature setting was attained, susceptibility ...
Whereas dissolution of magnetite associated with the pyritization of organic-rich sediments has been documented by several workers (e.g., Canfield and Berner, 1987), instances of the reverse process (magnetite replacement of pyrite) during the latter stages of diagenesis have also been reported (Reynolds, 1990; Suk et al., 1990).
Here we report a case study on the Luohe deposit. In the melanocratic-alteration zone, the composition of magnetite (including trace elements Ti, V, Mg, Mn), pyroxene (Mg, Fe 2+, Fe 3+, Al 2 O 3), plagioclase (An x Ab 1 − x), pyrite (Co, Ni) and apatite (F, CeO 2 + Y 2 O 3 + La 2 O 3) changes with depth.The isotherms of hydrothermal fluids determined from fluid …
Qian et al. (2009 Qian et al. (, 2010 presented an experimental study on the sulfidation of magnetite to form pyrite/marcasite under hydrothermal conditions (90e300 C, …
The present study focuses on the bulk geochemistry and the mineral chemistry of pyrite, chalcopyrite, magnetite, and titanite. Pyrite and chalcopyrite are the most abundant ore minerals at Vathi and are related to potassic, propylitic, and sericitic hydrothermal alterations (A-and D-veins), as well as to the late-stage epithermal overprint (E ...