The past research trend of the Mineralogical Society of Japan and the personal research activity are reviewed, and the view of the future is presented toward the progress of the Japan Association of Mineralogical Sciences.

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Recent advances in petrologic studies on kelyphite and symplectite, the reaction textures in metamorphic rocks, are reviewed. Kelyphitization of garnet is a phase transition phenomenon accompanied by a ‘long-range’ material transfer between garnet and olivine crystals. The microstructure of kelyphite is mostly constructed at the reaction front via ‘short-range’ material transfer along the garnet crystal surfaces and by the topotaxial crystal growth of pyroxenes and spinel. The ‘law of normality’ and the ‘principle of constant volume’ of the kelyphitization are proposed. Structural similarities among the kelyphites, symplectites, pearlite (of Fe-C alloy) and columnar joints, developed in basaltic lavas, are pointed out and discussed. In general discussions, I re-define ‘petrography’ as the science of rock texture and discuss in a more general context its relation to ‘tectonics’ in solid earth sciences.

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