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Journal Article

Interpretation of Raman spectra of the zircon–hafnon solid solution

Anja Maria Grüneberger, Christian Schmidt, Sandro Jahn, Dieter Rhede, Anselm Loges, Max Wilke
Published: 01 November 2016
European Journal of Mineralogy (2016) 28 (4): 721–733.
DOI: https://doi.org/10.1127/ejm/2016/0028-2551
...Anja Maria Grüneberger; Christian Schmidt; Sandro Jahn; Dieter Rhede; Anselm Loges; Max Wilke Abstract Zircon (ZrSiO 4 ), hafnon (HfSiO 4 ) and five intermediate compositions were synthesized from a Pb silicate melt. The resulting crystals were 20–300 µm in size and displayed sector and growth...
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View PDF for article title, Interpretation of Raman spectra of the zircon–<span class="search-highlight">hafnon</span> solid solution
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Journal Article

Hydrothermal Synthesis of Columbite-(mn), Tantalite-(mn), Hafnon, and Zircon At 800–850 °c and 200 Mpa

Alysha G. McNeil, Robert L. Linnen, Roberta L. Flemming
Published: 01 November 2015
The Canadian Mineralogist (2015) 53 (6): 1073–1081.
DOI: https://doi.org/10.3749/canmin.1400077
...Alysha G. McNeil; Robert L. Linnen; Roberta L. Flemming Fully ordered columbite-(Mn), tantalite-(Mn), hafnon, and zircon were successfully synthesized using an acid solution of 6N:1N (N = normal) HF:H 2 SO 4 and stoichiometric oxide mixtures. The mixtures and solutions were sealed and placed...
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View PDF for article title, Hydrothermal Synthesis of Columbite-(mn), Tantalite-(mn), <span class="search-highlight">Hafnon</span>, and Zircon At 800–850 °c and 200 Mpa
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Journal Article

Extreme fractionation from zircon to hafnon in the Koktokay No. 1 granitic pegmatite, Altai, northwestern China

Rong Yin, Ru Cheng Wang, Ai-Cheng Zhang, Huan Hu, Jin Chu Zhu, Can Rao, Hui Zhang
Published: 01 October 2013
American Mineralogist (2013) 98 (10): 1714–1724.
DOI: https://doi.org/10.2138/am.2013.4494
... the presence of hafnian zircon to zirconian hafnon. Large HfO 2 content variations of up to 34.8 wt% were also observed within single zoned crystals. We suggest that the increase of HfO 2 in the magmatic zircon from 9.4 wt% in the contact zone to 19.5 wt% in the cleavelandite–quartz–spodumene zone mainly...
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View PDF for article title, Extreme fractionation from zircon to <span class="search-highlight">hafnon</span> in the Koktokay No. 1 granitic pegmatite, Altai, northwestern China
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Journal Article

A high-pressure Raman spectroscopic study of hafnon, HfSiO 4

Bouchaib Manoun, Robert T. Downs, Surendra K. Saxena
Published: 01 November 2006
American Mineralogist (2006) 91 (11-12): 1888–1892.
DOI: https://doi.org/10.2138/am.2006.2070
...Bouchaib Manoun; Robert T. Downs; Surendra K. Saxena Abstract Raman spectra of synthetic HfSiO 4 were determined to pressures of 38.2 GPa. Changes in the spectra indicate that HfSiO 4 undergoes a room-temperature phase transition from the hafnon structure ( I 4 1 / amd space group) to the scheelite...
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View PDF for article title, A high-pressure Raman spectroscopic study of <span class="search-highlight">hafnon</span>, HfSiO 4
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Journal Article

Free energy of formation of zircon and hafnon

Hugh St.C. O’Neill
Published: 01 July 2006
American Mineralogist (2006) 91 (7): 1134–1141.
DOI: https://doi.org/10.2138/am.2006.2071
... of 1430 K for the martensitic phase transition between the tetragonal and monoclinic forms of ZrO 2 (baddeleyite), with an enthalpy of transition of 8.67 kJ/mol. The same experimental approach was used also to determine the free energy of formation of hafnon (HfSiO 4 ). The entropy of hafnon ( S 0 298K...
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View PDF for article title, Free energy of formation of zircon and <span class="search-highlight">hafnon</span>
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Journal Article

Crystal structure of synthetic hafnon, HfSiO 4 , comparison with zircon and the actinide orthosilicates

J. Alexander Speer, Brian J. Cooper
Published: 01 August 1982
American Mineralogist (1982) 67 (7-8): 804–808.
...J. Alexander Speer; Brian J. Cooper Abstract A crystal structure refinement of a synthetic hafnon, HfSiO 4 , space group I 4 1 / amd with a = 6.5725(7)Å, c = 5.9632(4)Å, Z = 4, D = 6.97 gm cm −3 , produced positional parameters for oxygen of y = 0.0655(13) and z = 0.1948(14) at R = 0.054. Hafnon...
View PDF for article title, Crystal structure of synthetic <span class="search-highlight">hafnon</span>, HfSiO 4 , comparison with zircon and the actinide orthosilicates
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Raman frequencies of HfSiO4 as a function of pressure. Up to 18.7 GPa, HfSiO4, has the hafnon structure. The appearance of a new vibrational mode at 618 cm−1 at the pressure of 20.6 GPa indicates that the transition to scheelite-structured hafnon has occurred.

Raman frequencies of HfSiO 4 as a function of pressure. Up to 18.7 GPa, Hf...

Published: 01 November 2006
F igure 3. Raman frequencies of HfSiO 4 as a function of pressure. Up to 18.7 GPa, HfSiO 4 , has the hafnon structure. The appearance of a new vibrational mode at 618 cm −1 at the pressure of 20.6 GPa indicates that the transition to scheelite-structured hafnon has occurred.
Journal Article

The solubility of Nb-Ta-Zr-Hf-W in granitic melts with Li and Li + F; constraints for mineralization in rare metal granites and pegmatites

Robert L. Linnen
Journal: Economic Geology
Published: 01 November 1998
Economic Geology (1998) 93 (7): 1013–1025.
DOI: https://doi.org/10.2113/gsecongeo.93.7.1013
... on the solubilities of columbite (MnNb 2 O 6 ), zircon (ZrSiO 4 ), hafnon (HfSiO 4 ), and hbnerite (MnWO 4 ) in granitic melts was also investigated. The haplogranitic melt compositions used in these experiments have constant mole percent Si and Al, and the Al/(Li + Na + K) ratio was 1.0 for all experiments, i.e...
View PDF for article title, The solubility of Nb-Ta-Zr-Hf-W in granitic melts with Li and Li + F; constraints for mineralization in rare metal granites and pegmatites
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Ambient-pressure Raman spectra for HfSiO4 (hafnon structure = *) starting material and for the sample quenched from 38.2 GPa and 300 K, which has converted to the scheelite-structured HfSiO4 phase (arrows). Peak assignments for the two spectra are given in Tables 1 and 2. The high-pressure resulting spectrum is clearly distinct from the spectrum obtained from the hafnon (starting material) and similar to the reidite spectrum decompressed from the zircon phase transformation.

Ambient-pressure Raman spectra for HfSiO 4 (hafnon structure = *) starting...

Published: 01 November 2006
F igure 1. Ambient-pressure Raman spectra for HfSiO 4 (hafnon structure = *) starting material and for the sample quenched from 38.2 GPa and 300 K, which has converted to the scheelite-structured HfSiO 4 phase (arrows). Peak assignments for the two spectra are given in Tables 1 and 2
Image
Experimental procedure for the synthesis of zircon, hafnon, and five intermediate compositions. (a) Schematic sketch of the capsules used for the synthesis. (b) Temperature–time path of the syntheses.

Experimental procedure for the synthesis of zircon, hafnon, and five interm...

Published: 01 November 2016
Fig. 1 Experimental procedure for the synthesis of zircon, hafnon, and five intermediate compositions. (a) Schematic sketch of the capsules used for the synthesis. (b) Temperature–time path of the syntheses.
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(a) Comparison between experimental spectra of zircon and hafnon end-member compositions and theoretical spectra from DFT calculations as indicated. For both compositions, different spectra were computed for a structure optimized at 0 GPa and for another structure optimized using the experimental density at ambient conditions as a constraint. (b) Variation of theoretical Raman spectra as a function of composition. Data shown were simulated at 0 GPa. The intermediate spectrum for Hfn0.5 was derived for a hypothetical ordered structure, where one of the two Zr atoms in the tetragonal unit cell was replaced by Hf. The lower graphs show a zoom of the upper ones, magnifying the low-intensity bands. (online version in colour)

(a) Comparison between experimental spectra of zircon and hafnon end-member...

Published: 01 November 2016
Fig. 10 (a) Comparison between experimental spectra of zircon and hafnon end-member compositions and theoretical spectra from DFT calculations as indicated. For both compositions, different spectra were computed for a structure optimized at 0 GPa and for another structure optimized using
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μXRD DATA FROM HAFNON AND ZIRCON EXPERIMENTS

Published: 01 November 2015
TABLE 6. μXRD DATA FROM HAFNON AND ZIRCON EXPERIMENTS
Image
Raman spectra through the phase transition from hafnon to scheelite-structured HfSiO4. The spectrum at 20.6 GPa shows the first appearance of a vibration of the scheelite-structured phase at 618 cm−1, and the spectrum at 25.5 GPa shows the appearance of a second peak in the scheelite-structured phase at 525 cm−1. The peak observed at 214 cm−1 (1 atm) became undetectable and the 351.3 cm−1 peak disappeared after 25.5 GPa.

Raman spectra through the phase transition from hafnon to scheelite-structu...

Published: 01 November 2006
F igure 2. Raman spectra through the phase transition from hafnon to scheelite-structured HfSiO 4 . The spectrum at 20.6 GPa shows the first appearance of a vibration of the scheelite-structured phase at 618 cm −1 , and the spectrum at 25.5 GPa shows the appearance of a second peak
Image
Schematic phase diagram showing crystallization of zircon-hafnon solid solution. Note that as zircon crystallizes, Zr/Hf in the remaining melt decreases.

Schematic phase diagram showing crystallization of zircon-hafnon solid solu...

Published: 01 October 2006
F ig . 1. Schematic phase diagram showing crystallization of zircon-hafnon solid solution. Note that as zircon crystallizes, Zr/Hf in the remaining melt decreases.
Journal Article

ZIRCONIUM AND HAFNIUM IN MINERALS OF THE COLUMBITE AND WODGINITE GROUPS FROM GRANITIC PEGMATITES

Petr Černý, T. Scott Ercit, Sten-Anders Smeds, Lee A. Groat, Ron Chapman
Published: 01 April 2007
The Canadian Mineralogist (2007) 45 (2): 185–202.
DOI: https://doi.org/10.2113/gscanmin.45.2.185
... by Zr/Hf. The Zr/Hf value in the (Nb,Ta)-oxide minerals generally corresponds to its range in associated zircon–hafnon. Considerable depolymerization of highly fractionated, (F, B, P)- and H 2 O-rich pegmatite-forming melts, in part alkaline in boundary layers (particularly significant in final stages...
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View PDF for article title, ZIRCONIUM AND HAFNIUM IN MINERALS OF THE COLUMBITE AND WODGINITE GROUPS FROM GRANITIC PEGMATITES
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Journal Article

Thorite: An Oddity in Phase Stability Amongst the Zircon-Structured Orthosilicates at High Pressures

Andrew C. Strzelecki, Jason L. Baker, Stella Chariton, Xiaodong Zhao, Vitali Prakapenka, David Bollinger, Sohan Ahmed, Jeffrey Fortner, Stephanie Szenknect, Adel Mesbah, John S. McCloy, Choong-Shik Yoo, Rodney C. Ewing, Nicolas Dacheux, Hongwu Xu, Xiaofeng Guo
Published: 17 January 2025
American Mineralogist (2025)
DOI: https://doi.org/10.2138/am-2024-9443
... the largest unit cell volume among tetravalent metal orthosilicates. The pressure derivatives of the vibrational modes of thorite were found to be consistent with those previously reported for other orthosilicates ( e.g. , zircon, hafnon, stetindite, and coffinite), while having the smallest Grüneisen...
View PDF for article title, Thorite: An Oddity in Phase Stability Amongst the Zircon-Structured Orthosilicates at High Pressures
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Early Publication
Image
Dependence of ZrO2 and HfO2 contents (wt.%) on the composition of melts saturated with zircon and hafnon, respectively. a, 800 °C (Linnen and Keppler, 2002); b, 1400 °C (Ellison and Hess, 1986). Linear-dependence equations and correlation coefficients are also given.

Dependence of ZrO 2 and HfO 2 contents (wt.%) on the composition of melts...

Published: 01 May 2020
Fig. 7. Dependence of ZrO 2 and HfO 2 contents (wt.%) on the composition of melts saturated with zircon and hafnon, respectively. a , 800 °C ( Linnen and Keppler, 2002 ); b , 1400 °C ( Ellison and Hess, 1986 ). Linear-dependence equations and correlation coefficients are also given.
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High-mass resolution spectra (m/Δm = 4500) of high-U zircon BP-1 (Buff Peak; ~3 wt% UO2), low-U zircon G42792 (~24 ppm U), synthetic cubic zirconia, hafnon, and epoxy mounting medium.

High-mass resolution spectra (m/Δm = 4500) of high-U zircon BP-1 (Buff Peak...

Published: 01 April 2007
F igure 2. High-mass resolution spectra (m/Δm = 4500) of high-U zircon BP-1 (Buff Peak; ~3 wt% UO 2 ), low-U zircon G42792 (~24 ppm U), synthetic cubic zirconia, hafnon, and epoxy mounting medium.
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Raman spectra of scheelite-structured HfSiO4 upon release of pressure to room conditions. The transformation of hafnon to a scheelite-structured HfSiO4 type is quenchable. The inset shows that the high-frequency SiO4 internal modes of the scheelite-structured HfSiO4 are not resolved until pressures below 5.5 GPa are reached.

Raman spectra of scheelite-structured HfSiO 4 upon release of pressure to ...

Published: 01 November 2006
F igure 4. Raman spectra of scheelite-structured HfSiO 4 upon release of pressure to room conditions. The transformation of hafnon to a scheelite-structured HfSiO 4 type is quenchable. The inset shows that the high-frequency SiO 4 internal modes of the scheelite-structured HfSiO 4
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XZ projections of the displacement vectors of the three external modes Eg(II), B1g(II) and Eg(III) obtained from the ab initio simulations. The B1g(II) mode is purely translational, whereas the Eg modes of zircon have both translational and rotational components. For hafnon, Eg(II) is predominantly translational and Eg(III) rotational. (online version in colour)

XZ projections of the displacement vectors of the three external modes Eg(I...

Published: 01 November 2016
Fig. 11 XZ projections of the displacement vectors of the three external modes Eg(II), B1g(II) and Eg(III) obtained from the ab initio simulations. The B1g(II) mode is purely translational, whereas the Eg modes of zircon have both translational and rotational components. For hafnon, Eg(II