Actinolite and hornblende commonly coexist in metabasite of upper greenschist-lower amphibolite facies. Two contradictory interpretations for the coexistence of two calcic amphiboles are suggested, that is, miscibility gap and transitional loop between actinolite and hornblende. We determined the space group of actinolite obtained from a greenschist of the Sanbagawa belt in central Shikoku. The greenschist was taken from lower metamorphic temperature area than that of the hornblende first appearance. Weissenberg and precession photographs indicate that the actinolite have C-lattice, and the existence of the center of symmetry is confirmed by treating the reflected X-ray intensities obtained by 4-circle diffractometer with statistical method (Nz method). The space group of the actinolite is C2/m. Since the actinolite has the same space group as that of hornblende, no crystallographic transformation can be considered in calcic amphibole. Hence, the coexistence of actinolite and hornblende should be explained by the miscibility gap between them.

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Chromian aegirine – aegirine-augite, phengite and allanite occur in blueschists, which are interbedded with serpentinite conglomerates, in the Ise area of the Sanbagawa belt, central Japan. Aggregates of chromian phengite±sodic pyroxene are scattered in the blueschists, and often include detrital chromian spinel. Sodic pyroxene in the aggregate shows solid solution between aegirine and kosmochlor components with a maximum 12.8 wt.% Cr₂O₃ (kosmochlor component = 38 mol%). Sodic pyroxene also occurs as individual crystal in the matrix, and has lower Cr₂O₃ (up to 0.7 wt.%). Phengite has a maximum 17.8 wt.% Cr₂O₃ showing a substitution of Cr for Al in octahedral sites. Allanite occurs in an aggregate of chromian phengite, sodic pyroxene and detrital chromian spinel, and contains up to 7.5 wt.% Cr₂O₃. Chromium in sodic pyroxene, phengite and allanite is derived from detrital chromian spinel. Distinct difference in Cr₂O₃ content between sodic pyroxenes in the aggregate and matrix suggests limited diffusion of Cr during the recrystallization.

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Firstly, the preparation of the thin specimen with a semi-spherical curvature 50 μm in thickness, where the compositional graded layer is put into between the epitaxial GaAs_0.6, P_0.4 layer and the GaAs substrate, is described. Secondly, the X-ray Laue method with white X-rays is applied to the curvature radius measurement of this specimen, having the radius of 20 to 73 cm. Thirdly, the X-ray Laue method using the characteristic X-rays to this curved specimen is devised to observe the microstructure in diffraction spots. The modified Leonhard chart to bring the specimen to the characteristic Bragg angle position is devised by us. Finally, the Burgers vector of the dislocations is identified to be ⟨110⟩ type, and the reason of the image sharpness of the dislocations is discussed.

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