Microcrystalline kaolinite has been rapidly synthesized in a specially designed pressure vessel rotated on rollers with grinding media. Starting material is sealed together with water and grinding media in a PTFE crucible covered by a stainless steel jacket, and heated and rotated in an oven with rollers. The synthesis process is hastened not only by temperature but also by continuous milling of the starting material and agitation of the reaction. The synthesis of kaolinite from weathered granite was studied in detail. Feldspathic granite powder, aluminum chloride solution and alumina beads were sealed in this vessel, and then rotated and heated for 2-8 days at 180°, 200° and 220°C under an autogenous vapor pressure. Yield of kaolinite increased with increases in temperature and duration time, and with decreases in the amount of granite. The duration time was shortened by approximately one-half of the stationary runs. Crystallite size of the produced kaolinite was smaller than that of stationary runs.

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The application of high resolution NMR in mineralogical and geochemical sciences has been developed deeply in a recent decade. It gives new insights into the structures and dynamic properties of silicates, aluminosilicates and zeolites. This review will briefly summarize some fundamental aspects of the theory and experimental practice of NMR spectroscopy and application of NMR methods to mineralogical and geochemical problems. Although cited examples are limited, the detailes could be found in excellent textbooks and review papers referenced in this paper.

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EXAFS spectroscopy and application to mineralogical problems are briefly reviewed. Local structure analysis of olivine solid solution Mg₂SiO₄-Fe₂SiO₄ is shown for example.

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In recent years, infrared-and Raman-microspectroscopic methods are widely used in the field of material science. As compared with other microanalytical techniques such as EPMA, AES and SIMS, which are essentially the techniques of elementary analysis, the characteristics of the infrared-and Raman-n rospectroscopy are that these techniques provide the structural information of the object. In the present article, the .zpplications of the infrared-and Raman-microspectroscopy to the characterization of inorganic materials, especially to that of minerals, have been reviewed.

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The spatial distribution of paramagnetic and impurities, point defects, radiation effects and orientation of crystal axes is shown in some crystals of zircon, barite, aragonite, apatite, synthetic diamond, and anorthite to demonstrate the usefulness of a microwave scanning ESR microscope which we have recently developed. The feature and principle of this new imaging method is presented with some applications to mineral sciences. New information which can not be obtained with other imaging methods such as EPMA, SIMS, and luminescence becomes available with this ESR microscope. A systematic application of an ESR microscope to mineral sciences is strongly hoped.

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Secondary ion mass spectrometry (SIMS) has become useful in the fields of geo-and cosmo-sciences as well as other various fields of industries, medicine, pharmacy, biology, etc. In geo-and cosmo-sciences, one of the merits of in situ isotopic analysis of SIMS is particularly significant. Applications of SIMS to diffusion study, age determination, investigation of isotopic anomaly are briefly reviewed. A development of a new SIMS with high mass resolution which is now proceeding in Naruto University of Education is described in section 5.

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A new analysis method on X-ray diffraction has been developed to study local structure of a long-range ordered crystal. The shell structure factor is defined here in order to extract the X-ray intensity by resonant scattering from the total scattered intensity. The method can make visible a kind of atom where the K-or L-shell electrons undergo dominant resonant scattering near the absorption edge. Because the other atoms remain transparent, the positional shift of particular atoms from their averaged position can be detected in crystallographically unique sites. Local structure of orthopyroxene, (Co, Ni, Zn) Si0₃ is discussed as an example.

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Aluminum foil specimens were immersed in neutral phosphate solutions with C_an=10^-4-10^-1 M and doulbly distilled water (DDW) for 60 min at 99.5°C, and the formation behavior of hydroxide films on the surface was examined by gravimetry, chemical analysis, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and impedance measurements. In DDW, two-layer hydroxide films were observed with film formation efficiency, η, of 1.0, and in phosphate solutions, thin single-layer hydroxide films were observed with η=0.7-0.9. At C_an=10^-2 kmol/m³, the film thickness showed a minimum and η a maximum. The XPS results showed that phosphates are incorporated in the outer part of the films formed in phosphate solutions, and that the phosphate incorporation increases with C_an. For all the films impedance measurements suggested the existence of an oxide layer with ca. 2.5 nm thickness at the interface between the hydroxide film and the metal substrate. The role of phosphate ions in the formation of hydroxide films is discussed in terms of dissolution and stabilization of the film with aluminum-phosphate complexes.

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