Contributions to Mineralogy and Petrology

, Volume 164, Issue 2, pp 341–358 | Cite as

Experimental Na/K exchange between alkali feldspar and an NaCl–KCl salt melt: chemically induced fracturing and element partitioning

  • G. Neusser
  • R. AbartEmail author
  • F. D. Fischer
  • D. Harlov
  • N. Norberg
Original Paper


The exchange of Na+ and K+ between alkali feldspar and a NaCl–KCl salt melt has been investigated experimentally. Run conditions were at ambient pressure and 850 °C as well as 1,000 °C. Cation exchange occurred by interdiffusion of Na+ and K+ on the feldspar sub-lattice, while the Si–Al framework remained unaffected. Due to the compositional dependence of the lattice parameters compositional heterogeneities resulting from Na+/K+ interdiffusion induced coherency stress and associated fracturing. Depending on the sense of chemical shift, different crack patterns developed. For the geometrically most regular case that developed when potassic alkali feldspar was shifted toward more sodium-rich compositions, a prominent set of cracks corresponding to tension cracks opened perpendicular to the direction of maximum tensile stress and did not follow any of the feldspar cleavage planes. The critical stress needed to initiate fracturing in a general direction of the feldspar lattice was estimated at ≤0.35 GPa. Fracturing provided fast pathways for penetration of salt melt or vapor into grain interiors enhancing overall cation exchange. The Na/K partitioning between feldspar and the salt melt attained equilibrium values in the exchanged portions of the grains allowing for extraction of the alkali feldspar mixing properties.


Alkali feldspar Cation exchange Chemically induced fracturing Element partitioning 



This work was funded by the Deutsche Forschungsgemeinschaft project AB 314/2-1 and by the Austrian Science foundation, FWF project I 474-N19, both in the framework of the research unit FOR 741-DACH. We thank Herbert Kroll for his advice regarding experimental procedure and for fruitful discussion. Furthermore we thank Richard Wirth for his help on the TEM and Dieter Rhede for help on the electron microprobe.

Supplementary material

410_2012_741_MOESM1_ESM.pdf (34 kb)
PDF (34 KB)


  1. Abart R, Petrishcheva E, Rhede D, Wirth R (2009) Exsolution by spinodal decomposition II: Perthite formation during slow cooling of anatexites from Ngoronghoro, Tanzania. Am J Sci 309:450–475. doi: 10.2475/06.2009.02 CrossRefGoogle Scholar
  2. Abart R, Petrishcheva E, Kässner S, Milke R (2009) Perthite microstructure in magmatic alkali feldspar with oscillatory zoning;Weinsberg Granite, Upper Austria. Mineral Petrol 97:251–263. doi: 10.1007/s00710-009-0090-1 CrossRefGoogle Scholar
  3. Bass JD (1995) Elasticity of minerals, glasses, and melts. AGU Reference Shelf 2. American Geophysical UnionGoogle Scholar
  4. Behrens H, Johannes W, Schmalzried H (1990) On the mechanisms of cation diffusion processes in Ternary Feldspars. Phys Chem Minerals 17:62–78CrossRefGoogle Scholar
  5. Brown WL, Parsons I (1988) Zoned ternary feldspars in the Klokken intrusion: exsolution microtextures and mechanisms. Contrib Miner Petrol 98:444454CrossRefGoogle Scholar
  6. Christoffersen R, Yund R, Tullis J (1983) Inter-difrusion of K and Na in alkali feldspars: diffusion couple experiments. Am Mineral 68:1126–1133Google Scholar
  7. Fuhrman ML, Lindsley DH (1988) Ternary-feldspar modeling and thermometry. Am Mineral 73:3–4Google Scholar
  8. Hovelmann J, Putnis A, Geisler T, Schmidt B, Golla-Schindler U (2010) The replacement of plagioclase feldspars by albite: observations from hydrothermal experiments. Contrib Mineral Petrol 159:43–59CrossRefGoogle Scholar
  9. Hovis GL, Delbove F, Bose MR (1991) Gibbs energies and entropies of K-Na mixing for alkali feldspar from phase equilibrium data: implications for feldspar solvi and short range order. Am Mineral 76:913–927Google Scholar
  10. Jamtveit B, Putnis C, Malthe-Sorenssen A (2009) Reaction induced fracturing during replacement processes. Contrib Mineral Petrol 157:127–133. doi: 10.1007/s00410-008-0324-y CrossRefGoogle Scholar
  11. Kroll H, Ribbe PH (1983) Lattice parameters, composition and Al,Si order in alkali feldspars. In: Ribbe PH (ed) Feldspar Mineral Rev Mineral 2:57–100Google Scholar
  12. Kroll H, Schmiemann I, von Coelln G (1986) Alklai feldspar solid-solutions. Am Mineral 71:1–16Google Scholar
  13. Larche FC, Cahn JW (1982) The effect of self-stress on diffusion in solids. Acta Metallica 30:1335–1845CrossRefGoogle Scholar
  14. Manning JR (1968) Diffusion kinetics for atoms in crystals. Van Nostrand, New YorkGoogle Scholar
  15. Norberg N, Neusser G, Wirth R, Harlov D (2011) Microstructural evolution during experimental albitization of K-rich alkali feldspar. Contrib Mineral Petrol 162:531–546. doi: 10.1007/s00410-011-0610-y CrossRefGoogle Scholar
  16. Nye JP (1985) Physical properties of crystals. Oxford University Press, New YorkGoogle Scholar
  17. Orville PM (1963) Alkali ion exchange between vapor and feldspar phases. Am J Sci 267:201–237CrossRefGoogle Scholar
  18. Orville PM (1967) Unit-cell parameters of the microcline—low albite and the sanidine-high albite solid solution series. Am Mineral 52:55–86Google Scholar
  19. Parsons I (1978) Feldspar and fluids in cooling plutons. Mineral Mag 42:1–17CrossRefGoogle Scholar
  20. Parsons I, Thompson P, Lee MR, Cayzer N (2005) Alkali feldspar microtextures as provenance indicators in siliciclastic rocks and their role in feldspar dissolution during transport and diagenesis. J Sedimant Res 75:921–942CrossRefGoogle Scholar
  21. Parsons I, Lee M (2009) Mutual replacement reactions in alkali feldspars I: microtextures and mechanisms. Contrib Mineral Petrol 157:641–661CrossRefGoogle Scholar
  22. Petrishcheva E, Abart R (2009) Exsolution by spinodal decomposition: I: evolution equation for binary mineral solutions with anisotropic interface energy. Am J Sci 309:431–449. doi: 10.2475/06.2009.01 CrossRefGoogle Scholar
  23. Petrovic R (1973) Effect of coherency stress on mechanism of reaction albite+k+ reversible k-feldspar+na+ and on mechanical state of resulting feldspar. Contrib Mineral Petrol 41:151–170CrossRefGoogle Scholar
  24. Plümper O, Putnis A (2009) The complex hydrothermal history of granitic rocks: multiple feldspar replacement reactions under subsolidus conditions. J Petrol 30:967–987CrossRefGoogle Scholar
  25. Putnis A (2002) Mineral replacement reactions: from macroscopic observations to microscopic mechanisms. Mineral Mag 66:689–708CrossRefGoogle Scholar
  26. Putnis A (2009) Mineral replacement reactions. Rev Mineral Geochem 70:87–124CrossRefGoogle Scholar
  27. Robin P (1974) Stress and strain in cryptoperthite lamellae and the coherent solvus of alkali feldspar. Am Mineral 59:1299–1318Google Scholar
  28. Smith JV, Brown W (1988) Feldspar minerals, volume 1: crystal structures, physical, chemical, and microtextural properties. Springer, BerlinGoogle Scholar
  29. Svoboda J, Fischer FD, Fratzl P (2002) Diffusion in multi-component systems with no or dense sources and sinks for vacancies. Acta Mater 50:1369–1381. doi: 10.1016/S1359-6454(01)00443-8 CrossRefGoogle Scholar
  30. Thompson JB Jr, Waldbaum DR (1968) Mixing properties of sanidine crystalline solutions. I. Calculations based on ion-exchange data. Am Mineral 53:1965–1999Google Scholar
  31. Tullis J, Yund R (1979) Calculation of coherent solvi for alkali feldspar, iron-free clinopyroxene, nepheline-kalsilite, and hematite-ilmenite. Am Mineral 64:1063–1074Google Scholar
  32. Voll G, Evangelakakis C, Kroll H (1991) Revised 2-feldspar geothermometry applied to Sri-Lankan feldspars. Precambr Res 66:351–377. doi: 10.1016/0301-9268(94)90058-2 CrossRefGoogle Scholar
  33. Waldbaum DR (1969) Thermodynamic mixing properties of NaCl–KCI liquids. Geochimi et Cosmochim Acta 33:1415–1427CrossRefGoogle Scholar
  34. Worden RH, Walker FDL, Parsons I, Brown WL (1990) Development of microporosity, diffusion channels and deuteric coarsening in perthitic alkali feldspar. Contrib Mineral Petrol 104:507–515CrossRefGoogle Scholar
  35. Yund R (1984) Alkali Feldspar exsolution: Kinetics and dependence on alkali interdiffusion. In: Brown WL (ed) Feldspars and feldspathoids: structure, properties, and occurrences. Dordrecht, D. Reidel Publishing Company, NATO Advanced Science Institute Series C, v. 137:281–315Google Scholar
  36. Yund R, Tullis J (1983) Strained cell parameters for coherent lamellae in alkali feldspars and iron-free pyroxene. Neues Jahrbuch f Mineralgie 1983:22–34Google Scholar

Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • G. Neusser
    • 1
  • R. Abart
    • 2
    Email author
  • F. D. Fischer
    • 3
  • D. Harlov
    • 4
  • N. Norberg
    • 4
  1. 1.Institute of Geological SciencesFree University BerlinBerlinGermany
  2. 2.Department of Lithospheric ResearchUniversity of ViennaViennaAustria
  3. 3.Institute of MechanicsMontanuniversität LeobenLeobenAustria
  4. 4.Helmholtzzentrum PotsdamDeutsches GeoForschungsZentrumPotsdamGermany

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