Report of the Association Internationale pour l'Etude des Argiles (AIPEA) Nomenclature Committee for 1996

Abstract

The most recent report of the AIPEA Nomenclature Committee involved the definition and use of the terms 'clay' and 'clay mineral'; see Guggenheim & Martin (1995; 1996). Additional items acted upon by this committee are reported here.

Authigenic kaolin and illitic minerals during burial diagenesis of sandstones: a review

“…As recommended by Guggenheim et al (1997), these two terms are used hereafter as mineral names even though both species are in fact polytypes. Kaolin is used hereafter as a mineral group name to describe the subgroup of dioctahedral 1:1 phyllosilicates.…”

Preparation and characterization of antibacterial silver/vermiculites and silver/montmorillonites

“…The vermiculite in comparison with mica has a lower layer charge and the iron is oxidized. Vermiculites are generally termed (according to the joint nomenclature committees AIPEA and CMS) on the basis of a negative layer charge, which is higher than 0.6 while for smectites it is between 0.2 and 0.6 per half unit cell (Guggenheim et al, 1997;Guggenheim et al, 2006;Bergaya and Lagaly, 2006). The negative layer charge of montmorillonites results from an octahedral substitution of magnesium by iron because of the sporadic tetrahedral substitution of Al 3+ for Si 4+ (Grim and Kulbicky, 1961).…”

Vermiculite: Structural Properties and Examples of the Use

“…hydroxide sheet Mg6(OH) Vermiculites are generally trioctahedral and are termed (according to the joint nomenclature committees AIPEA and CMS) on the basis of a negative layer charge, which is between 0.6 to 0.9 p.f.u. [4,7,8]. The negative layer charge of vermiculites results from the substitution of Si 4+ by trivalent cations in tetrahedral positions [9,10].…”