Prossima pubblicazione.
Referenza:
▪ Nagashima, M., Cametti, G., Armbruster, T. (2018): Crystal chemistry of julgoldite, a mineral series of the pumpellyite group: Re-investigation of Fe distribution and hydrogen-bonding. European Journal of Mineralogy, 30, (in press).
Crystal chemistry of julgoldite: Re-investigation of Fe distribution and hydrogen-bonding
- Marco E. Ciriotti
- Messaggi: 31675
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
Crystal chemistry of julgoldite: Re-investigation of Fe distribution and hydrogen-bonding
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
- Marco E. Ciriotti
- Messaggi: 31675
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
Re: Crystal chemistry of julgoldite: Re-investigation of Fe distribution and hydrogen-bonding
Referenza:
▪ Nagashima, M., Cametti, G., Armbruster, T. (2018): Crystal chemistry of julgoldite, a mineral series of the pumpellyite group: Re-investigation of Fe distribution and hydrogen-bonding. European Journal of Mineralogy, 30, (in press).
Abstract:
Single-crystal X-ray crystal-structure refinements and electron-microprobe analyses of two julgoldite samples, in one case complemented by Mössbauer spectroscopy to determine the Fe valence distribution, yielded the compositions Ca2.00X(Fe2+0.44Fe3+0.29Mg0.17Al0.10)Y(Fe3+0.82Al0.18)2Si3O10.39(OH)3.61 (Bombay) and Ca2.00X(Fe0.67Mg0.16Al0.17)Y(Fe3+0.81Al0.19)2Si3O14 − n(OH)n (4 ≥ n ≥ 3) (Kreimbach/Kaulbach), respectively. Structure refinements also allowed specification of the system of hydrogen bonds, which concur with those known for pumpellyite. A review of structural and chemical data for pumpellyite-group minerals including six julgoldite samples indicated that the length of the b axis is governed by the average size of ionic radii at the Y site, except for one sample of julgoldite-(Fe3+). Size effects of the concentration of “large” divalent cations (Mg, Fe) at the X site can be seen in the lateral extension of the (010) plane that acts as a buffer to accomodate the variable size of the X octahedra. Using unit-cell plots, the data suggest that five of the six tested julgoldite samples are julgoldite-(Fe2+) and only the one sample of the Bombay area studied by Artioli et al. (2003) is julgoldite-(Fe3+). Both samples studied in this paper were classified into julgoldite-(Fe2+). In contrast to pumpellyite samples sensu stricto, which exhibit a Me2+:Me3+ ratio of approximately 1:1, julgoldite samples may cover the whole range between Ca2X(Fe3+)Y(Fe3+)2Si3O11(OH)3 and Ca2X(Fe2+)Y(Fe3+)2Si3O10(OH)4.
▪ Nagashima, M., Cametti, G., Armbruster, T. (2018): Crystal chemistry of julgoldite, a mineral series of the pumpellyite group: Re-investigation of Fe distribution and hydrogen-bonding. European Journal of Mineralogy, 30, (in press).
Abstract:
Single-crystal X-ray crystal-structure refinements and electron-microprobe analyses of two julgoldite samples, in one case complemented by Mössbauer spectroscopy to determine the Fe valence distribution, yielded the compositions Ca2.00X(Fe2+0.44Fe3+0.29Mg0.17Al0.10)Y(Fe3+0.82Al0.18)2Si3O10.39(OH)3.61 (Bombay) and Ca2.00X(Fe0.67Mg0.16Al0.17)Y(Fe3+0.81Al0.19)2Si3O14 − n(OH)n (4 ≥ n ≥ 3) (Kreimbach/Kaulbach), respectively. Structure refinements also allowed specification of the system of hydrogen bonds, which concur with those known for pumpellyite. A review of structural and chemical data for pumpellyite-group minerals including six julgoldite samples indicated that the length of the b axis is governed by the average size of ionic radii at the Y site, except for one sample of julgoldite-(Fe3+). Size effects of the concentration of “large” divalent cations (Mg, Fe) at the X site can be seen in the lateral extension of the (010) plane that acts as a buffer to accomodate the variable size of the X octahedra. Using unit-cell plots, the data suggest that five of the six tested julgoldite samples are julgoldite-(Fe2+) and only the one sample of the Bombay area studied by Artioli et al. (2003) is julgoldite-(Fe3+). Both samples studied in this paper were classified into julgoldite-(Fe2+). In contrast to pumpellyite samples sensu stricto, which exhibit a Me2+:Me3+ ratio of approximately 1:1, julgoldite samples may cover the whole range between Ca2X(Fe3+)Y(Fe3+)2Si3O11(OH)3 and Ca2X(Fe2+)Y(Fe3+)2Si3O10(OH)4.
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
- Marco E. Ciriotti
- Messaggi: 31675
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
Re: Crystal chemistry of julgoldite: Re-investigation of Fe distribution and hydrogen-bonding
Pubblicazione effettuata:
Referenza:
▪ Nagashima, M., Cametti, G., Armbruster, T. (2018): Crystal chemistry of julgoldite, a mineral series of the pumpellyite group: Re-investigation of Fe distribution and hydrogen-bonding. European Journal of Mineralogy, 30, 721-731.
Referenza:
▪ Nagashima, M., Cametti, G., Armbruster, T. (2018): Crystal chemistry of julgoldite, a mineral series of the pumpellyite group: Re-investigation of Fe distribution and hydrogen-bonding. European Journal of Mineralogy, 30, 721-731.
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
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