Showing papers in "Clay science in 1979"

Summary of recommendations of aipea nomenclature committee

Abstract: Because of their small particle sizes and variable degrees of crystal perfection, it is not surprising that clay minerals proved extremely difficult to characterize adequately prior to the development of modern analytical techniques. Problems in characterization led quite naturally to problems in nomenclature, undoubtedly more so than for the macroscopic, more crystalline minerals. Popular adoption in the early 1950s of the X-ray powder diffractometer for clay studies helped to solve some of the problems of identification. Improvements in electron microscopy, electron diffraction and oblique texture electron diffraction, IR and DTA equipment, the development of nuclear and isotope technology, of high-speed electronic computers, of M6ssbauer spectrometers, and most recently of the electron microprobe and scanning electron microscope have all aided in the accumulation of factual information on clays. This, in turn, should facilitate eventual agreement on the nomenclature of clays. Probably the earliest attempt by clay scientists to reach agreement on nomenclature and classification on an international basis was at the International Soil Congress held in Amsterdam in 1950 (Brindley et al., 1951). Since that time national Nomenclature Committees have been established in many countries. Recommendations from these national groups have been considered every three years at the International Clay Conferences, first by the Nomenclature Sub-Committee of CIPEA (Comite International Pour l'Etude Des Argiles) and since 1966 by the Nomenclature Committee of AIPEA (Association Internationale Pour l'Etude des Argiles). These international committees in turn have worked closely with the Commission on New Minerals and Mineral Names of the I.M.A. (International Mineralogical Association). This summary of the recommendations made to date by the international nomenclature committees has been prepared in order to achieve wider dissemination of the decisions reached and to aid clay scientists in the correct usage of clay nomenclature. Some of the material in the present summary has been taken from an earlier summary by Bailey et al. (1971a).