D/H ratios and amounts of the water extracted from hornblende, biotite, muscovite and volcanic glass by step-wise heating under vacuum were measured and the D/H fractionation factors between released and remaining water in each step were calculated by the Rayleigh distillation model. Most of the dehydration of the hydrous silicates took place at temperatures higher than 700°C, while most of the water in dacitic glasses was released at temperatures lower than 600°C. The fractionation factors for the minerals were much less than unity, i.e., the remaining water is enriched in deuterium. The isotopic fractionation pattern of higher temperature fractions for the hydrous silicates could be represented by a single α value. The values for the glasses were quite close to unity and in the higher temperature fractions they are commonly larger than unity.

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The refractive indices of powdered materials were estimated under a polarizing microscope with an ultralong working distance objective lens of high magnification. The materials with various refractive indices (n_s=1.33-2.66) were suspended in the liquids and the plastic materials with various refractive indices (n_m=1.33-1.78). The image and relief depending on the difference of refractive indices, ?? n=|n_s-n_m|, were eliminated by enlarging the numerical aperture of substage condenser. The nearly proportional relation was found between ?? n and the numerical aperture at which the image and relief of particle could be eliminated, although there were the appreciable deviations due to the various factors such as size and shape of particle, focusing, illumination, thickness of cover glass and numerical aperture of objective lens. However, when these factors were fixed at suitable conditions, ?? n could be estimated with the accuracy less than ± 0.01 for the ?? n range from 0 to 0.25. This procedure will be called tentatively “Relief extinction method” and utilized for estimating the refractive indices of wide range by only a single medium of known refractive index.

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REE and trace metals in seven GSJ rock reference samples were determined by means of sequential type inductively coupled argon plasma/optical emission spectrophotometer (ICP). Separation and preconcentration of the REE and trace metals from an 1g sample digest are achieved by a nitric acid gradient cation exchange and hydrochloric acid anion exchange following Crock and Richte's method. Final solutions are 10 or 20ml for REE analysis and 200ml for trace metal analysis. Relative standard deviation and detection limit of REE analysis are demonstrated by the triplicate analysis of JB-lI and JG-1. REE and trace metal analyses of seven GSJ samples show comparable precision and accuracy, but Cr, Ni, and Zr analyses are not so in some cases.

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