scholarly journals Garnet-Vesuvianite Equilibrium in Rodingites from Dobšiná (Western Carpathians)

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 189
Author(s):  
Juraj Butek ◽  
Ján Spišiak ◽  
Stanislava Milovská
Keyword(s):  
Solid Solution ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Mineral Chemistry ◽  
Significant Degree ◽  
Western Carpathians ◽  
Mineral Association ◽  
Degree Of Hydration ◽  
Average Temperature ◽  
Low Degree

Intensively metasomatized rocks from serpentinized ultramafic tectonic fragments in Dobšiná, Western Carpathians, consist of typical rodingite mineral association: hydrated garnet, vesuvianite, diopside and clinochlore. Electron microprobe analysis (EMPA) and Micro-Raman analyses of the main minerals evidence complex mineralogical evolution and variable mineral chemistry. Garnet solid solution is dominated by grossular-andradite series, which demonstrates a significant degree of hydration, mainly for grossular rich garnet cores. Garnet is locally enriched in TiO2 (up to 13 wt%), possibly indicating a chemical relic of a Ti-oxide mineral. Younger, andradite-richer garnet rims demonstrate a low degree of hydration, suggesting a harder incorporation of an (OH)− anion into its crystal structure. Garnet chemical variations display an ideal negative correlation between Al and (Fe3+ + Ti). The most recent mineral phase is represented by euhedral vesuvianite (± chlorite), which crystallizes at the expense of the garnet solid solution. This reaction shows a well-equilibrated character and indicates a high extent of rodingitization process. Chlorite thermometry models suggest an average temperature of late rodingite (trans) formation of about 265 °C.

Unit-cell parameters for scapolite solid solutions and a discontinuity at Me75, ideally NaCa3[Al5Si7O24](CO3)

2013 ◽  
Vol 28 (4) ◽  
pp. 269-275
Author(s):  
Sytle M. Antao
Keyword(s):  
Solid Solution ◽  
Unit Cell Volume ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Unit Cell ◽  
Formula Unit ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters

Twenty-seven scapolite samples from various localities and with compositions between Me6–93 were obtained using electron microprobe analysis (EMPA). Their unit-cell parameters were obtained using synchrotron high-resolution powder X-ray diffraction (HRPXRD) data and Rietveld structure refinements using space group P42/n. The EMPA data show the well-known discontinuity at Me75. In addition, the unit-cell parameters, especially c, show a discontinuity at Me75 (=five Al atoms per formula unit, apfu), ideally NaCa3[Al5Si7O24](CO3), where the scapolite solid solution is divided into two (Me% = [Ca/(Ca + Na + K)] × 100). A maximum c parameter value occurs at Me37.5 (=four Al apfu ideally), where complete Al–Si, Na–Ca, and Cl–CO3 order occurs. The unit-cell volume, V, varies smoothly with Me% and Al apfu across the series.

scholarly journals Blue cancrinite from South-East Greenland

1994 ◽  
Vol 161 ◽  
pp. 5-10
Author(s):  
A Jensen ◽  
T.F.D Nielsen
Keyword(s):  
Solid Solution ◽  
Trace Elements ◽  
Spectral Analysis ◽  
Nepheline Syenite ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Solid Solution Series ◽  
Blue Colour ◽  
East Greenland ◽  
X Ray

Blue cancrinite intergrown with sodalite and albite has been found in nepheline syenite dykes in the Precambrian of South-East Greenland. Cabochons cut of the material show a blue colour with more or less pronounced aventurescence. Electron microprobe analysis and X-ray investigation have been carried out to establish the position in the cancrinite-vishnevite solid solution series. Trace elements have been determined by spectral analysis of the Greenland cancrinite as well as cancrinite from Litchfield Maine, USA and Bancroft. Ontario, Canada.

A Study of Natural Metamict Yttrium Niobate as Analogue of Actinide Ceramic Waste Form

2014 ◽  
Vol 1665 ◽  
pp. 313-318 ◽  
Author(s):  
Cao Qiuxiang ◽  
Anton I. Isakov ◽  
Liu Xiaodong ◽  
Sergey V. Krivovichev ◽  
Boris E. Burakov
Keyword(s):  
Electron Microscopy ◽  
Solid Solution ◽  
Single Phase ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Original Sample ◽  
X Ray Diffraction ◽  
Average Chemical Composition ◽  
X Ray ◽  
Scanning Electron

ABSTRACTNatural metamict mineral found as large (1-3 cm in size) homogeneous grains (as assumed, former single crystals), was investigated by X-ray powder diffraction (pXRD), high-temperature pXRD, scanning electron microscopy (SEM) and electron microprobe analysis (EMPA). The average chemical composition obtained by EMPA is (wt. %): Nb2O5 – 42.6; Ta2O5 – 4.4; TiO2 – 9.2; UO3 – 4.4; ThO2 – 1.0; MnO – 1.3; FeO – 19.4; Y2O3 – 16.6.The untreated (original) sample is X-ray amorphous. The sample remained amorphous after annealing at 400 °C for 1 hour. The sample became almost fully crystalline after annealing at 700 °C for 1 hour with an X-ray diffraction pattern similar to that of Fe-columbite (ICCD: 01-074-7356). Further annealing at 1000 °C and higher temperatures caused changes in the phase composition of the sample. It was proposed that under self-irradiation a single-phase U-Th-bearing solid solution, based on monocrystalline Y-niobate, became metamict but remained homogeneous without evidence of solid solution destruction. However, this metamict solid solution is unstable under thermal treatment and recrystallization.

Ternary feldspars: two-feldspar assemblages at P(H2O) = 5 kbar

1989 ◽  
Vol 53 (371) ◽  
pp. 347-355
Author(s):  
Rhian H. Jones
Keyword(s):  
Solid Solution ◽  
Electron Microprobe ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Liquidus Surface ◽  
Ternary Solid Solution ◽  
Heating Period ◽  
Early Stages ◽  
Tie Lines ◽  
Tie Line

AbstractIn a study of the liquidus surface in the silica-undersaturated part of the system Q-An-Ne-Ks at P(H2O) = 5 kbar, several two-feldspar plus liquid assemblages were obtained. The compositions of the feldspars were determined by electron microprobe analysis. The products of short runs (one or two days) consisted of fine intergrowths of two feldspars which may have crystallized during the heating period, or in the early stages of the run. Runs of four days were of sufficient length to coarsen these intergrowths such that individual euhedral crystals could be observed. However, analyses of the feldspar crystals from the longer runs showed a greater amount of ternary solid solution than expected. This may be attributed to the persistence of a small quantity of the second feldspar intergrown in the crystals. The slope of the tie-line joining one of the inferred pairs has been shown to be reproducible for gel and crystalline starting materials, hence the slopes of the tie-lines are believed to represent their equilibrium slopes.

scholarly journals Phase equilibria in Ho-Fe-Sn ternary system at 670 K

2020 ◽  
Vol 21 (2) ◽  
pp. 272-278
Author(s):  
L. Romaka ◽  
Yu. Stadnyk ◽  
V. V. Romaka ◽  
A. Horpenyuk
Keyword(s):  
Phase Diagram ◽  
Solid Solution ◽  
Isothermal Section ◽  
Ternary System ◽  
Electron Microprobe ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Structure Type ◽  
Binary Compound ◽  
X Ray

Interaction between the components in the Ho-Fe-Sn ternary system was studied using X-ray diffractometry, metallography and electron microprobe analysis. Isothermal section of the phase diagram was constructed at 670 K over the whole concentration range. Component interaction in the Ho-Fe-Sn system at 670 K results in the existence of one ternary compound HoFe6Sn6 which crystallizes in the YCo6Ge6 structure type (space group P6/mmm, a=0.53797(2),   c= 0.44446(2) nm). The interstitial-type solid solution HoFexSn2 (up to 8 at.% Fe) based on the HoSn2 (ZrSi2-type structure) binary compound was found. Solubility of Sn in the HoFe2 binary (MgCu2 structure type) extends up to 5 at. %.

Scanning Electron Microscopy and Electron Microprobe Analysis of Malignant Cell Cultures

1968 ◽  
Vol 26 ◽  
pp. 164-165
Author(s):  
R. I. Johnsson-Hegyeli ◽  
A. F. Hegyeli ◽  
D. K. Landstrom ◽  
W. C. Lane
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cell Cultures ◽  
Electron Microprobe ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Three Dimensional ◽  
Malignant Cell ◽  
Interference Microscopy ◽  
Scanning Electron

Last year we reported on the use of reflected light interference microscopy (RLIM) for the direct color photography of the surfaces of living normal and malignant cell cultures without the use of replicas, fixatives, or stains. The surface topography of living cells was found to follow underlying cellular structures such as nuceloli, nuclear membranes, and cytoplasmic organelles, making possible the study of their three-dimensional relationships in time. The technique makes possible the direct examination of cells grown on opaque as well as transparent surfaces. The successful in situ electron microprobe analysis of the elemental composition and distribution within single tissue culture cells was also reported.This paper deals with the parallel and combined use of scanning electron microscopy (SEM) and the two previous techniques in a study of living and fixed cancer cells. All three studies can be carried out consecutively on the same experimental specimens without disturbing the cells or their structural relationships to each other and the surface on which they are grown. KB carcinoma cells were grown on glass coverslips in closed Leighto tubes as previously described. The cultures were photographed alive by means of RLIM, then fixed with a fixative modified from Sabatini, et al (1963).

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