Part 2. Hydrocarbons, verified by high-temperature Micro-FTIR, are found to be included by the same anorthite and labradorite megacrysts containing native coppers, as described in Part 1, in basaltic rocks, from Japanese island arc and in the western continental margin of North America, respectively. A finding of Muntz metal (Cu₆₀Zn₄₀) within the anorthite megacryst offerred the establishment of Hume-Rothery's rule in nature. Concerning the genesis of native coppers coexistent with the hydrocarbon, the exsolution model fortified by their purity and oriented distribution has been suggested and can account for crystal growth of native coppers based on the theory of Ostwald ripening. While continental margins and Island arcs have geological and tectonical backgrounds common to each other, remarkable difference in morphology between fractured labradorites and euhedral anorthites seems to flare up in the power of the volcanic eruption. Moreover it proved that the corroded olivines within anorthite megacrysts hereupon have also a trace amount of hydrocarbons, detection of which discloses that the magmas crystallizing these anorthite and olivines contained the same hydrocarbons. Fe/Mg ratio of the corroded olivines, Sr-content and Sr-isotope ratio of anorthite megacrysts typical of arc-volcanism in Japan afford the lateral variations from the Japan trench to the Back arc side, and their geochemical behaviour witnesses the rapid crystallization of anorthite megacrysts and their corroded olivines in close association with the crust components and the slab-sediments subducted beneath the island arc. Review (2) must be highly speculative because of the paucity of experimental and natural evidences on the megacrysts and their inclusions. Nevertheless it is upbeat, and the key point is that island arc magmatism should be reconstructed as the petrochemical system containing transition metals (e.g. Cu and Zn), hydrocarbons and chlorines. This reconstruction must elicit the far-reaching effect of mixing the basaltic magma with the sea water and slab-sediments rich in metals. Advances in understanding the geochemical system that formed anorthite megacrysts have come from the mineralogical study of their active inclusions providing more questions than answers.

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Fluormicas have been synthesized by an internal resistance electric melting method. Because of their sizes and stable structures of the crystals those synthetic micas had a potential for cosmetic use. In them, synthetic fluorphlogopite(FPG)has been studied to be the best mica for cosmetics.The fluorphlogopite is chemically pure, and has a excellent lubricity and adhesiveness. The authors established the methods of its synthesis and pulverizing for cosmetic use. UV absorption is the most important item for cosmetics for e.g. protecting sunburn and suntan. The authors newly developed a method to synthesize an iron-rich fluorphlogopite which is more efficient to absorb UV-rays than common fluorphlogopite. It has presently been used in some commercial cosmetics.

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The role of minerals on the migration of radionuclides should be examined to clarify the geological barrier system for the estimation of the impact of geological disposal. Radionuclides are sorbed and fixed on/to minerals during migration in geosphere. This review provides the information on the sorption characteristics of cesium, strontium, cobalt and neptunium on minerals and the redistribution of cesium, strontium, cobalt, uranium and neptunium during alteration of primary minerals to secondary ones. Neptunium is irreversibly sorbed on smectite between pH 2 and 5, where neptunium is not desorbed from smectite with a 1 M KCl solution, but is desorbed with a 1 M HCl solution. Uranium is fixed to crystalline iron minerals during the weathering of chlorite to kaolinite and iron minerals. Cesium and cobalt changes their sorption characteristics during the alteration of smectite to illite, and are more tightly associated with the I/S interstratified mineral than those estimated based on the sorption behavior on the I/S interstratified mineral. Neptunium changes its sorption characteristics during the crystallization of amorphous iron minerals, and are more tightly associated with crystalline iron minerals than those sorbed on crystalline iron minerals.

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Studies on local structures around several 3d transition-metal ions in quenched melts and crystals with diopsidebased composition are briefly reviewed. Results obtained by different spectroscopic and diffraction techniques, i.e. XAFS, NMR, EELS, XRD and ED (ALCHEMI), are consistent with each other. The strong preference of Cr³⁺ to occur in sixfold coordination even in quenched melts, which is unlikely for others, can be explained by the large CFSE in a octahedral coordination. Thus Cr³⁺ ions are expected to behave as network modifier and have significant effects on crystallization processes. Measurement and analysis methods making use of different physical phenomena, developed in the last few decades, increase our knowledges on the role of these elements in magmatic processes and in materials science.

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