抄録
This paper concerns with the determination by quantitative chemical analysis, etc., of the minerals (2MgO⋅SiO2, MgO⋅SiO2, free MgO and free SiO2) which may exist in the process of the synthesis of forsterite from magnesium hydroxide and crystobalite.
The mixtures prepared for the molar ratio of about 2MgO⋅1.1SiO2 from magnesium hydroxide and silica gel or cristobalite were heated up to the temperatures, 700°-1550°C, at the interval of 40°C.
The samples so obtained using cristobalite as a siliceous starting material were subjected to quantitative analysis, whose method was based on the characteristics that cristobalite and enstatite are not affected, but magnesium and forsterite are soluble or decomposable by dilute hydrochloric acid.
It was confirmed that the quantities of each minerals existing in the specimen after various heat treatment could be measured successfully.
Such specimens were analysed by X-ray using internal standard, and by measuring the variation of the intensity of diffraction pattern.
From the results of chemical analysis and X-ray diffraction pattern the calibration curves were set up taking into consideration of the best condition of X-ray analysis.
The variation in the process of forsterite formation from other silicious starting materials, silica gel or quartz, were investigated quantitatively using above calibration curve.
