Clays and Clay Minerals

, Volume 58, Issue 5, pp 717–720 | Cite as

Comment on “The Role of H3O+ in the Crystal Structure of Illite” By F. Nieto, M. Melini, And I. Abad

  • Olivier VidalEmail author
  • Benoît Dubacq
  • Pierre Lanari


The arguments of Nieto et al. (2010) in favor of the incorporation of H3O+ rather than H2O in interlayer positions of illite are disputable. Stoichiometric arguments suggest that the excess water in the Silver Hill illite is in the form of H2O. Moreover, recent thermodynamic models assuming the incorporation of interlayer H2O in illite provide reasonable estimates of temperature and water content using the AEM/TEM analyses of Nieto et al. (2010).

Key Words

Composition Hydronium Illite Water 


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Copyright information

© Clay Minerals Society 2010

Authors and Affiliations

  1. 1.LGCA, Université Grenoble, CNRSGrenoble cedex 09France
  2. 2.Department of Earth SciencesUniversity of CambridgeCambridgeUK

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