Unusual sensitivity to grinding has been found in the orthohexagonal iron chlorites: in addition to the X-ray powder reflections becoming rapidly more diffuse, the positions of the (20l) reflections move to the higher angle sides or are replaced by new monoclinic (20l) bands. These changes may be due to displacements of the structural layers that take place on grinding. Some natural chlorites of lower crystallinity give patterns similar to some of the ground products.

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The radioactive equilibrium states in the uranium ores of the Ningyotoge mine were investigated in relation to their ionium content and to their microscopic features.
An analytical method of Io/U was examined and applied to the ores.The method is characterized by not being necessary to determine the chemical yield in the separation of thorium and by simplicity for obtaining the absolute value of Io/U. In order to investigate the states being different in phases of a specimen, variation of Io/Th-234 under chemical leaching was traced. Autoradiography and radioactivity measurements were also done.
The states of the radioactive equilibrium in the Ningyotoge ores are thought to be a results of the differentiation of thorium from uranium.This may occur by oxidation and chemical leaching and by crystallization of uranium minerals. The radiocolloid is explained as being a product of this differentiation. The radioactive nuclides included in the radiocolloid are ionium and its daughter products.

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Two specimens of alkali amphiboles (arfvedsonite from Greenland and riebeckite from Quincy, U. S. A.) were examined in detail by X-ray methods. Oscillation and Weissenberg photographs were taken about the b- and c-axes with CuK_α radiation. The C-setting of axes being taken, it was discovered that besides the ordinary rule of missing spectra required for the expected space group C2/m, the h0l reflections with l odd are completely missing, and the direct application of the extinction rules to these minerals leads to the space group C2/c. However as the result of the structure analysis, it was concluded that the newly added extinction rule is only apparent, and the space group of arfvedsonite and riebeckite are definitely C2/m, the same group as other amphiboles. The cause of this phenomenon was explained by the existence of local c-glide planes parallel to (010), offering the first experimental evidence of the Templeton effect.

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Natural pyrrhotite is classified into three types on the basis of its temperature dependency of magnetism. First, the peak-type pyrrhotite has the weakest magnetism among the three types, and its intensity of magnetization is within the range of 1.2 gausses to 18.8 gausses (the applied magnetic field H=10, 600 Oe.). The magnetization I of the peak-type pyrrhotite increases linearly with the increasing magnetic field H. A characteristic of this type is that the I-T curve has a single sharp peak at 220°C. Secondly, the magnetization of the weiss-type pyrrhotite having the strongest magnetism among the three reaches a saturated value within about 10, 000 Oe. of applied magnetic field, and its saturation magnetization lies between 103 gausses and 118 gausses. The I-T curve of this type of pyrrhotite shows the tendency of that of the ordinary Weiss-type, and its Curie point is at 305°C. Thirdly, the mixed-type pyrrhotite has an intermediate tendency in intensity of magnetization, the magnetization curve and the I-T curve each coming between those of the peak and the Weiss types.
A close relation exists among the above-mentioned magnetic properties of pyrrhotite, its chemical composition which lies between FeS_1•104 and FeS_1•158, and its crystal structure. It has been shown that the Weiss-type pyrrhotite and a part of the mixed-type one (I>100 gausses) have the Bertaut's monoclinic structure.
The I-T curves in the cooling process of the peak-type and the mixed-type pyrrhotites do not coincide with those of the heating process. This phenomenon results from an increase of the atomic ratio of sulphur of pyrrhotite in the latter process.
before and after heat treatment. The most appropriate explanation for this phenomenon may be to postulate some increment of the atomic ratio of sulphur of pyrrhotite due to the diffusion of free sulphur, which has been formed in connection with the surface oxidation of pyrrhotite at room temperature, into the inner part of the grains in the heating process.

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