Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-05T21:20:19.306Z Has data issue: false hasContentIssue false

Thermal expansion of highly silicic nepheline-kalsilite crystalline solutions

Published online by Cambridge University Press:  05 July 2018

G. L. Hovis*
Affiliation:
Department of Geology &, Environmental Geosciences, Lafayette College, Easton, PA 18042, USA
E. Person
Affiliation:
Department of Geology &, Environmental Geosciences, Lafayette College, Easton, PA 18042, USA
A. Spooner
Affiliation:
Department of Geology &, Environmental Geosciences, Lafayette College, Easton, PA 18042, USA
J. Roux
Affiliation:
Physique des Minéraux et des Magmas, IPGP, 4, place Jussieu, 75252 Paris cedex 05, France
*

Abstract

We have investigated the thermal expansion of nepheline-kalsilite crystalline solutions having 12.5% excess silicon relative to the stoichiometric composition. It is proposed that differences in the thermal expansion among various members of the series, and also between this series and a previously studied low-Si series, can be explained by three factors: (1) shrinkage of the tetrahedral rings caused by the substitution of Na for K, especially in the case of kalsilite, allows for greater expansion from the increased vibrational amplitude of Na ions with increasing temperature. (2) The occupancy of alkali sites by ions rather than vacancies draws tetrahedral rings inward via electrical attraction to these ions, providing the potential for greater expansion with ionic vibration as temperature increases. (3) Structural differences between nepheline and kalsilite, in particular the existence of two alkali sites in nepheline, account for the increased thermal expansion of K-enriched nepheline relative to Na-nepheline, as the occupation of the larger alkali position by K+ results in greater thermal expansion than is the case with Na+ occupancy of the same sites.

Type
Editorial
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Alderbert, P. and Traverse, J. P. (1984) A12O3 a high temperature thermal expansion standard. High Temperatures – High Pressures, 16, 127135.Google Scholar
Carpenter, M. A. and Cellai, D. (1996) Microstructures and high-temperature phase transitions in kalsilite. American Mineralogist, 81, 561584.CrossRefGoogle Scholar
Courbion, G. and Ferey, G. (1988) Na2Ca3Al2F14: A new example of a structure with ‘independent F-’ —A new method of comparison between fluorides and oxides of different formula. Journal of Solid State Chemistry, 76, 426431.CrossRefGoogle Scholar
de Dombal, R. F. and Carpenter, M. A. (1993) High-temperature phase transitions in Steinbach tridymite. European Journal of Mineralogy, 5, 607622.CrossRefGoogle Scholar
Evain, M., Deniard, P., Jouanneaux, A. and Brec, R. (1993) Potential of the INEL X-ray position-sensitive detector. A general study of the Debye-Scherrer setting. Journal of Applied Crystallography, 26, 563569.CrossRefGoogle Scholar
Henderson, C. M. B. and Roux, J. (1976) The thermal expansions and crystallographic transformations of some synthetic nephelines. Pp. 6069 in: Progress in Experimental Petrology, NERC Report 3 (Biggar, G. M., editor).Google Scholar
Henderson, C. M. B. and Roux, J. (1977) Inversions in sub-potassic nephelines.. Contributions to Mineralogy and Petrology, 61, 279298.CrossRefGoogle Scholar
Henderson, C. M. B. and Taylor, D. (1982) The structural behaviour of the nepheline family: (1) Sr and Ba aluminates (MA12O4). Mineralogical Magazine, 45, 111127.CrossRefGoogle Scholar
Henderson, C. M. B. and Taylor, D. (1988) The structural behaviour of the nepheline family: (3) Thermal expansion of kalsilite. Mineralogical Magazine, 52, 708711.CrossRefGoogle Scholar
Holland, T. J. B. and Redfern, S. A. T. (1997) Unit-cell refinement: Changing the dependent variable, and use of regression diagnostics. Mineralogical Magazine, 61, 6577.CrossRefGoogle Scholar
Hovis, G. L. and Roux, J. (1993) Thermodynamic mixing properties of nepheline-kalsilite crystalline solutions. American Journal of Science, 293, 11081127.CrossRefGoogle Scholar
Hovis, G. L. and Roux, J. (1999) Thermodynamics of excess silicon in nepheline and kalsilite crystalline solutions. European Journal of Mineralogy, 11, 815827.CrossRefGoogle Scholar
Hovis, G. L. and Crelling, J. A. (2000) The effects of excess silicon on immiscibility in the nepheline-kalsilite system. American Journal of Science, 300, 238249.CrossRefGoogle Scholar
Hovis, G. L., Spearing, D. R., Stebbins, I., Roux, J. and Clare, A. (1992) X-ray powder diffraction and 23Na, 27A1, and 29Si MAS-NMR investigation of nepheline-kalsilite crystalline solutions. American Mineralogist, 77, 1929.Google Scholar
Hovis, G. L., Brennan, S., Keohane, M. and Crelling, J. (1999) High-temperature X-ray investigation of sanidine-analbite crystalline solutions. Thermal expansion, phase transitions, and volumes of mixing. The Canadian Mineralogist, 37, 701709.Google Scholar
Hovis, G. L., Crelling, I, Wattles, D., Dreibelbis, B., Dennison, A., Keohane, M. and Brennan, S. (2003) Thermal expansion of nepheline-kalsilite crystalline solutions. Mineralogical Magazine, 67, 535546.CrossRefGoogle Scholar
Kawahara, A., Andou, Y., Marumo, F. and Okuno, M. (1987) The crystal structure of the high temperature form of kalsilite (KAlSiO4) at 950°C. Mineralogical Journal, 13, 260270.CrossRefGoogle Scholar
Merlino, S. (1984) Feldspathoids: Their average and real structures. Pp. 435470 in: Feldspars and Feldspathoids (Brown, W. L., editor). Reidel Publishing Company, Dordrecht, The Netherlands.CrossRefGoogle Scholar
Parrish, W. (1953) X-ray reflection angle tables for several standards. Technical Report No. 68, Philips Laboratories Incorporated, Irvington on Hudson, New York.Google Scholar
Roux, J. and Volfinger, M. (1996) Mesures precises a l'aide d'un detecteur courbe. Journal de Physique IV, 6, colloque C4, 127134.Google Scholar
Sahama, Th.G. (1962) Perthite-like exsolution in the nepheline-kalsilite system. Norsk geologisk Tidsskrift, 43, 168179.Google Scholar
Salje, E. K. H., Graeme-Barber, A. and Carpenter, M. A. (1993) Lattice parameters, spontaneous strain and phase transitions in Pb3(PO4)2 . Acta Crystallographica, B49, 387392.CrossRefGoogle Scholar