Synthesis and crystal chemistry of mukhinite, V-analogue of clinozoisite on the join Ca2Al3Si3O12(OH)–Ca2Al2VSi3O12(OH)

Nagashima, Mariko; Nishio–Hamane, Daisuke; Nakano, Nobuhiko; Kawasaki, Toshisuke

doi:10.1007/s00269-018-0988-4

Cited by 5 publications

(4 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The crystal structure of REE-rich mukhinite from South Urals is similar to the structures of other epidote-supergroup minerals (Armbruster et al , 2006) as well as the synthetic analogue of mukhinite (Nagashima et al , 2019). The epidote-type structure is based on chains of two types (Chain 1 and Chain 2) formed by edge-sharing octahedra ( M 2O 6 and M 1O 6 octahedra, respectively).…”

Section: Resultssupporting

confidence: 60%

“…Taking into account that the ionic radius of [ 6 ] Cr 3+ (0.615 Å) is intermediate between those of [ 6 ] Al 3+ and [ 6 ] V 3+ (0.535 and 0.640 Å, respectively) (Shannon, 1976), we suppose that a minor admixture of Cr 3+ , rather than V 3+ , occurs at the M 2 site. The incorporation of the large Mg 2+ cation with the ionic radius of 0.72 Å (Shannon, 1976) in the M 3 site is confirmed by the increased mean bond length in comparison with synthetic mukhinite with M 3 = V 3+ 0.62 Al 3+ 0.38 and < M 3–O> = 2.023 Å (Nagashima et al , 2019).…”

Section: Resultsmentioning

confidence: 95%

“…The structure determination and refinement were carried out using the JANA2006 program package (Petricek et al , 2014). The initial model for the mukhinite structure refinement was based on the atomic coordinates of its synthetic analogue (Nagashima et al , 2019). Atomic scattering factors and anomalous dispersion corrections from the International Tables for Crystallography (Prince, 2004) were used.…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Crystal chemistry and origin of REE-bearing mukhinite from carbonate veins of the Svetlinsky gold deposit, South Urals, Russia

Korinevsky

Чуканов

Aksenov

et al. 2022

MinMag

View full text Add to dashboard Cite

A rare earth element (REE)-, Cr- and Mg-bearing variety of the vanadium epidote-group mineral mukhinite occurs in a calcite–dolomite carbonatite dyke cutting metamorphosed volcano-sedimentary rocks exposed in the walls of the quarry of the Svetlinsky gold deposit, South Urals. This mineral was found in a paragene assemblage including native sulphur, phlogopite and fluorophlogopite, together with accessory pyrite, other sulfides and sulfosalts, gold, Cr- and V-bearing muscovite, margarite, Cr- and V-bearing dravite, fluoro-tremolite, actinolite, fluoro-pargasite, anhydrite, apatite, uranium hydroxides, V-rich titanite, V- and Nb-rich rutile, spinel and corundum. The contents of ΣREE2O3 and V2O3 in mukhinite vary in the ranges of 4.01–9.69 and 5.34–7.46 wt.%, respectively. A Raman spectrum of REE-rich mukhinite is provided. The main schemes of isomorphic substitutions in mukhinite are ΣREE + Mg ↔ Ca + Al and V+Cr ↔ Al. The crystal structure of REE-rich mukhinite has been studied by single-crystal X-ray diffraction analysis. The mineral is monoclinic, with the space group P21/m, and unit-cell parameters are: a = 8.8972(11) Å, b = 5.6221(6) Å, c = 10.1519(12) Å, β = 115.169° and V = 459.60(11) Å3. The crystal structure of REE-rich mukhinite is similar to that of its synthetic analogue; the refined crystal-chemical formula of the sample studied is (Z = 2): { A 1Ca A 2(Ca0.8REE0.2)}{ M 1(Al0.95Cr0.05) M 2Al M 3[(V,Cr)3+0.40Al0.35Mg0.25]}(Si2O7)(SiO4)O(OH).

show abstract

Section: Resultssupporting

confidence: 60%

Section: Resultsmentioning

confidence: 95%

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Crystal chemistry and origin of REE-bearing mukhinite from carbonate veins of the Svetlinsky gold deposit, South Urals, Russia

Korinevsky

Чуканов

Aksenov

et al. 2022

MinMag

View full text Add to dashboard Cite

show abstract

“…cupy M3, although they may partially substitute for M1 Al even before entirely filling M3 (e.g. Dollase, 1969Dollase, , 1971Dollase, , 1973Giuli et al, 1999;Langer et al, 2002;Akasaka, 2004, 2010;Nagashima et al, 2009Nagashima et al, , 2019.…”

Section: Introductionmentioning

confidence: 99%

Optimal Raman-scattering signal for estimating the Fe³⁺ content on the clinozoisite–epidote join

Nagashima

Mihailova²

2023

Eur. J. Mineral.

Self Cite

View full text Add to dashboard Cite

Abstract. To provide a tool for fast estimation of the Fe3+ content in Ca2(Al, Fe3+)3Si3O12(OH) epidote grains, including in thin sections and crude-rock samples, we applied Raman spectroscopy to 33 areas from 15 natural samples with Fe3+ ranging from 0.22 to 1.13 atoms per formula unit (apfu), the chemistry of which was independently determined by wavelength-dispersive electron microprobe analysis (WD-EPMA). The Raman spectra were collected from the very areas subjected to WD-EPMA. We have analysed both the OH-stretching region (3215–3615 cm−1) and the spectral range generated by the framework vibrations (15–1215 cm−1). Similarly to the IR spectra, the Raman peaks in the OH-stretching region shift toward higher wavenumbers with increasing Fe. However, the quantification of Fe3+ based on OH-stretching Raman peaks can be hindered by the multicomponent overlapping and significant intensity variations with the crystal orientation. Among the Raman signals generated by framework vibrations, the position of four peaks (near 250, 570, 600, and 1090 cm−1) exhibit a steady linear regression with the increase in Fe content (in apfu). However, the peak near 250 cm−1 attributed to MO6 vibrations also depends on the crystal orientation and therefore is not always well resolved, which worsens the accuracy in Fe-content determination based on its position. The peaks near 570, 600, and 1090 cm−1 arise from Si2O7 vibrational modes, and although their intensities also vary with the crystal orientation, all three signals are well resolved in a random orientation. However, among the three Si2O7-related signals, the 570 cm−1 peak is the sharpest (peak width <10 cm−1) and is easily recognized as a separate peak. Hence, we propose to use the position of this peak as a highly reliable parameter to estimate the Fe content, via the linear trend given as ω570=577.1(3)-12.7(4)x, where ω is the wavenumber (cm−1) and x is Fe content (apfu), with accuracy ± 0.04 Fe3+ apfu. The peaks near 600 and 1090 cm−1 may be complementarily used for the Fe estimate, based on the following relations: ω600=611.6(2)-13.8(4)x and ω1090=1098.8(3)-13.5(5)x. Analyses of the effect of Sr as a substitution for Ca and Cr at the octahedral sites indicate that contents of Sr <0.12 apfu do not interfere with the quantification of Fe via the ω570 (x) relation, whereas Cr >0.16 apfu leads to overestimation of Fe; Cr presence can be recognized however by the broadening of the peaks near 95 and 250 cm−1.

show abstract

The structural state of Finnish Cr- and V-bearing clinozoisite: insights from Raman spectroscopy

et al. 2021

View full text Add to dashboard Cite

Synthesis and crystal chemistry of mukhinite, V-analogue of clinozoisite on the join Ca2Al3Si3O12(OH)–Ca2Al2VSi3O12(OH)

Cited by 5 publications

References 36 publications

Crystal chemistry and origin of REE-bearing mukhinite from carbonate veins of the Svetlinsky gold deposit, South Urals, Russia

Crystal chemistry and origin of REE-bearing mukhinite from carbonate veins of the Svetlinsky gold deposit, South Urals, Russia

Optimal Raman-scattering signal for estimating the Fe³⁺ content on the clinozoisite–epidote join

The structural state of Finnish Cr- and V-bearing clinozoisite: insights from Raman spectroscopy

Contact Info

Product

Resources

About

Synthesis and crystal chemistry of mukhinite, V-analogue of clinozoisite on the join Ca2Al3Si3O12(OH)–Ca2Al2VSi3O12(OH)

Cited by 5 publications

References 36 publications

Crystal chemistry and origin of REE-bearing mukhinite from carbonate veins of the Svetlinsky gold deposit, South Urals, Russia

Crystal chemistry and origin of REE-bearing mukhinite from carbonate veins of the Svetlinsky gold deposit, South Urals, Russia

Optimal Raman-scattering signal for estimating the Fe3+ content on the clinozoisite–epidote join

The structural state of Finnish Cr- and V-bearing clinozoisite: insights from Raman spectroscopy

Contact Info

Product

Resources

About

Optimal Raman-scattering signal for estimating the Fe³⁺ content on the clinozoisite–epidote join