scholarly journals Efflorescent Sulfate Crystallization on Fractured and Polished Colloform Pyrite Surfaces: A Migration Pathway of Trace Elements

Minerals ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 12
Author(s):  
Dimitrina Dimitrova ◽  
Vassilka Mladenova ◽  
Lutz Hecht
Keyword(s):  
Electron Microscopy ◽  
Trace Elements ◽  
Inductively Coupled Plasma ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
X Ray ◽  
Inductively Coupled ◽  
Migration Pathway ◽  
Plasma Mass Spectrometry ◽  
Scanning Electron

The colloform pyrite variety incorporates many trace elements that are released in the environment during rapid oxidation. Colloform pyrite from the Chiprovtsi silver–lead deposit in Bulgaria and its oxidation efflorescent products were studied using X-ray diffractometry, scanning electron microscopy, electron microprobe analysis, and laser ablation inductively coupled plasma mass spectrometry. Pyrite is enriched with (in ppm): Co (0.1–964), Ni (1.8–3858), Cu (2.9–3188), Zn (3.1–77), Ag (1.2–1771), As (8179–52,787), Se (2.7–21.7), Sb (48–17792), Hg (4–2854), Tl (1.7–2336), Pb (13–7072), and Au (0.07–2.77). Gypsum, anhydrite, szomolnokite, halotrichite, römerite, copiapite, aluminocopiapite, magnesiocopiapite, coquimbite, aluminocoquimbite, voltaite, and ammoniomagnesiovoltaite were identified in the efflorescent sulfate assemblage. Sulfate minerals contain not only inherited elements from pyrite (Cr, Fe, Co, Ni, Cu, Zn, Ag, In, As, Sb, Hg, Tl, and Pb), but also newly introduced elements (Na, Mg, Al, Si, P, K, Ca, Sc, Ti, V, Mn, Ga, Rb, Sr, Y, Zr, Sn, Cs, Ba, REE, U, and Th). Voltaite group minerals, copiapite, magnesiocopiapite, and römerite incorporate most of the trace elements, especially the most hazardous As, Sb, Hg, and Tl. Colloform pyrite occurrence in the Chiprovtsi deposit is limited. Its association with marbles would further restrict the oxidation and release of hazardous elements into the environment.

A Technical and Analytical Study of Two Silver Plates in the Collection of the J.Paul Getty Museum

1990 ◽  
Vol 185 ◽  
Author(s):  
David Scott
Keyword(s):  
Inductively Coupled Plasma ◽  
Analytical Study ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
X Ray ◽  
Inductively Coupled ◽  
Close Relationship ◽  
Plasma Mass Spectrometry ◽  
Non Destructive

AbstractTwo silver plates in the collection of the J. Paul Getty Museum were studied by non-destructive x-ray fluorescence spectroscopy, inductively-coupled plasma-mass spectrometry, xradiography, optical metallography, electron microprobe analysis and lead isotopic composition. One plate depicts a scene of philosophical discourse (the ‘Philosopher plate’) and the other an aged fisherman with his catch (the ‘Fisherman plate’). Both plates have designs on the fronts made not by repousse but by a combination of working and annealing followed by carving to shape. Technical and analytical results are described which support the attribution of a date in the early centuries AD. There are several differences between the two plates, such as the way in which the footring has been made and attached. Both, however, have thick corrosion crusts and have suffered intergranular corrosion. Determination of trace elements, such as zinc and gold, together with the method of manufacture suggests that both plates are ancient. Lead isotopic data for the two plates is different, with the Philosopher plate showing a close relationship to other Byzantine objects, even though a Renaissance date had been suggested.

Topaz as an important host for Ge in granites and greisens

2013 ◽  
Vol 77 (4) ◽  
pp. 403-417 ◽  
Author(s):  
K. Breiter ◽  
N. Gardenová ◽  
T. Vaculovič ◽  
V. Kanický
Keyword(s):  
Mass Spectrometry ◽  
Trace Elements ◽  
Inductively Coupled Plasma ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
Important Host ◽  
Ga Content

AbstractThe composition of topaz from different granites and greisen in the Krušné Hory/Erzgebirge area was investigated using electron microprobe analysis (EMPA) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). All topaz grains are rich in F (17.9 19.8 wt.%, 1.73 1.90 a.p.f.u.) and the most important minor/trace elements are P, Ge and Ga. Contents of P up to 1 wt.% P2O5 (0.025 a.p.f.u.) were found in topaz from the strongly peraluminous P-rich magmatic systems at Podlesí. Regardless of genetic type, topaz from granites typically contains 50 100 ppm Ge. The greatest amounts (up to 204 ppm Ge) were found in topaz from quartz-topaz-apatite greisen in Krásno. In fractionated granites and greisens, topaz is calculated to contain 23 87% of the bulk Ge content in the rock. In contrast, topaz does not concentrate Ga. The Ga content of topaz (typically 5 35 ppm in S-type granites, <10 ppm Ga in A-type granites) is usually smaller than the bulk Ga content of the rock. In addition, up to 16 ppm Sc, 23 ppm Sn and >400 ppm Fe may be present.

scholarly journals Acetalization of Glycerol with Citral over Heteropolyacids Immobilized on KIT-6

Catalysts ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 81
Author(s):  
José Castanheiro
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Fixed Time ◽  
Tungstophosphoric Acid ◽  
X Ray Diffraction ◽  
Glycerol Conversion ◽  
X Ray ◽  
Inductively Coupled ◽  
Catalytic Stability ◽  
Scanning Electron

Glycerol acetalization with citral was studied using a heteropolyacid (tungstophosphoric acid) supported on KIT-6, as a catalyst, at 100 °C. Different catalysts were synthesized. Catalysts were characterized by scanning electron microscopy (SEM), inductively coupled plasma (ICP), X-ray diffraction (XRD), attenuated total refletion-Fourier transform infrared spectroscopy (ATR-FTIR), and potentiometric titrations. At a fixed time, the glycerol conversion increased with the H3PW12O40 (PW) on KIT-6. PW4-KIT-6 material had a higher conversion than other catalysts. The optimization of glycerol’s acetalization with citral was studied under the PW4-KIT-6 catalyst. After 5 h, it was found that, at T = 100 °C, with m = 0.3 g of solid, molar glycerol:citral = 1:2.25, the conversion of glycerol was 89%. Moreover, the PW4-KTI-6 catalyst showed good catalytic stability.

scholarly journals Partitioning and Surficial Segregation of Trace Elements in Iron Oxides in Hydrothermal Fluid Systems

Minerals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 57
Author(s):  
Nikolay Smagunov ◽  
Vladimir Tauson ◽  
Sergey Lipko ◽  
Dmitriy Babkin ◽  
Taisa Pastushkova ◽  
...  
Keyword(s):  
Trace Elements ◽  
Inductively Coupled Plasma ◽  
Absorption Spectrometry ◽  
X Ray ◽  
Force Microscopy ◽  
Inductively Coupled ◽  
Atomic Force ◽  
Fluid Systems ◽  
Nonautonomous Phase ◽  
Plasma Mass Spectrometry

Partitioning experiments were done by hydrothermal synthesis of crystals containing trace elements (TEs) by internal sampling of fluid at the temperature of 450 °C and pressure of 1 kbar. The crystal phases obtained were magnetite, hematite, and Ni-spinel, which were studied using X-ray diffraction (XRD), X-ray electron probe microanalysis (EPMA), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), atomic absorption spectrometry (AAS), and atomic force microscopy (AFM). The solutions from the sampler’s fluid probes were analysed by AAS for TEs included elements of the iron group plus aluminium. The highest co-crystallisation coefficients of TE and Fe between mineral and fluid (DTE/Fe) in magnetite were measured for V, Al, Ni and Cr (in decreasing order of n units in value), a lower value was observed for Co (2 × 10−1), and still lower values for Ti, Zn, and Mn (n × 10−2–10−3). In hematite, DTE/Fe values were highest for Al and V (order of n units in value), while lower values characterised Ti, Cr, and Co (n × 10−1–10−3), and the lowest values were exhibited by Cu, Mn, and Zn (n × 10−5). Copper was confirmed to be the most incompatible with all minerals studied; however, Cu had a high content on crystal surfaces. This surficial segregation contributes to the average TE concentration even when a thin layer of nonautonomous phase (NAP) is enriched in the element of interest. The accumulation of TEs on the surface of crystals increased bulk content 1–2 orders of magnitude above the content of structurally-bound elements even in coarse crystals. The inverse problem—evaluation of TE/Fe ratios in fluids involved in the formation of magnetite-containing deposits—revealed that the most abundant metals in fluids were Fe followed by Mn, Zn, and Cu, which comprised 10 to 30% of the total iron content.

Electron microprobe analysis of the distribution of silicon in the leaves of Selaginella emmeliana

1980 ◽  
Vol 58 (23) ◽  
pp. 2459-2466 ◽  
Author(s):  
Nancy G. Dengler ◽  
Eric Y-C. Lin
Keyword(s):  
Electron Microscopy ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Cell Types ◽  
Preliminary Survey ◽  
Leaf Epidermis ◽  
Abaxial Side ◽  
X Ray ◽  
Tangential Wall ◽  
Scanning Electron

Scanning electron microscopy and X-ray microanalysis of the ventral leaves of Selaginella emmeliana demonstrated high levels of silicon in the marginal sclereids and about one-half the abaxial epidermal cells. Although both of these cell types bear rows of knobs or warts on the outer tangential wall, the X-ray spectra indicate that silicon is distributed throughout the wall and that it is not concentrated in these projections. In S. emmeliana, stomata are confined to a band of low silicon cells overlying the midrib on the abaxial side of the leaf. A small proportion of these stomata also contain high levels of silicon and are characterized by a constricted stomatal aperture. A preliminary survey of three other species of Selaginella indicates that accumulation of silicon in the leaf epidermis is characteristic for each.

scholarly journals Use of the System S2o3 (2-) -O2 for the Leaching of Precious Metals Contained in a Mineral From Molango in the State of Hidalgo, Mexico

2018 ◽  
Vol 14 (3) ◽  
pp. 48 ◽  
Author(s):  
Edmundo Roldán-Contreras ◽  
Juan Hernández-Ávila ◽  
Eduardo Cerecedo-Sáenz ◽  
Ma. Isabel Reyes-Valderrama ◽  
Eleazar Salinas-Rodríguez
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Energy Dispersive Spectrometry ◽  
Precious Metals ◽  
X Rays ◽  
X Ray ◽  
Plasma Spectrometry ◽  
Inductively Coupled ◽  
Inductively Coupled Plasma Spectrometry ◽  
Scanning Electron

The newer tendencies of research, related with the leaching of precious metals, involves the use of non toxic reagents that allows the leaching of a mineral of sedimentary origin using the system S2 - O3 2- - O2. Prior to thisprocess, the mineral was characterized by Scanning Electron Microscopy (SEM) in conjunction with Energy Dispersive Spectrometry of X – rays (EDS), X- ray mapping. Finally, the chemical composition was executed by Inductively Coupled Plasma Spectrometry (ICP). According to the results obtained, it was possible to determine that the mineral studied has adequate contents of gold, palladium, silver, and platinum. And after the leaching process, it could be possible to leach the gold and palladium that it contains, getting recoveries of 90% and 85 %, respectively. In the case of silver, a redissolution or precipitation could occur during the first minutes of reaction.

scholarly journals Metal Threads from the Fourteenth-Century Slabbed Graves at the Plateau of Eski-Kermen

2021 ◽  
pp. 229-245
Author(s):  
Anna V. Antipenko ◽  
Anastasia Yu. Loboda ◽  
Elzara A. Khairedinova ◽  
Artem M. Ismagulov ◽  
Ekaterina S. Vashchenkova ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Fourteenth Century ◽  
Inductively Coupled Plasma ◽  
High Grade ◽  
Inductively Coupled ◽  
Inner Surface ◽  
Plasma Mass Spectrometry ◽  
The One ◽  
Scanning Electron ◽  
Thin Band

This paper presents the results of the study of metal threads found in the fourteenth-century burials in slabbed graves located atop of the plateau of Eski-Kermen. The inductively coupled plasma mass spectrometry determined the metal of the threads in question as high-grade silver. The results of scanning electron microscopy of the surface morphology of the artefacts allowed the one to suggest a variant of reconstruction of the sequence of technological operations in the manufacture of the metal threads in question. The feature of all the metal threads under study is very even outer and inner surface and stable thickness and width of the metal band. In all cases, gold inclusions were stretched in the mass of metal along the long edge of the bands. Cast metal was flattened into a thin band. Parallel scratches along the butt end of the threads suggest that rolled out metal was cut with a tool with a thin, sharp blade leaving scratches along the course of the blade. Semi-finished products were wound onto an organic core. The threads found in the slabbed graves atop of the plateau of Eski-Kermen were spun silver threads wound onto a silk core. Technologically, these threads correspond to the products of Mediterranean workshops. The location of the metal threads in the burial indicates that they were used in the embroidering of the collar and neck.

scholarly journals How Microanalysis Can Be Discriminant on Black Pompeian Wares

Crystals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 879
Author(s):  
Laura Medeghini ◽  
Silvano Mignardi ◽  
Giorgia Di Fusco ◽  
Michela Botticelli ◽  
Fulvio Coletti ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Grain Size ◽  
Analytical Approach ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Specific Production ◽  
X Ray ◽  
Black Layer ◽  
Scanning Electron

In the present work the advantages of punctual approaches are discussed in the discrimination of black wares from the Sanctuary of Venus Fisica (Pompeii, Italy), dated between the 2nd and 1st century BC. Black-gloss ware and "bucchero" samples are analyzed by a multi-analytical approach including optical microscopy (OM), X-ray powder diffraction (XRPD), scanning electron microscopy with Energy Dispersive Spectroscopy (SEM-EDS) and electron microprobe analysis (EMPA) to investigate the mineralogical and petrographic features of these artefacts. Grain size, firing conditions and potter’s expertise influenced the final appearance of the superficial decorative black layer. In addition, punctual chemical analysis was fundamental to verify the archaeological indication of specific production sites.

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