Unpolarized spectrum of a new mineral (Ba, Sr) VOSi₂O₆ was recorded in the range of 5, 000-30, 000cm^-1. The peaks at 12, 100cm^-1, 15, 000cm^-1 (shoulder), and around 21, 800cm^-1 were assigned to the transitions from the ground level d_x²-y² to the excited levels d_yz, d_xz, and d_z² respectively, using the energy level values calculated directly based on pure crystal field theory for distorted square pyramidal coordination of C_2v symmetry.

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The first occurrence of vaesite in Japan is described from the Kurokotype deposits of the Kosaka mine in Northeast Japan. Microprobe analysis showed its chemical composition to be very close to NiS₂, though it con-tains small amounts of Fe, Cu, and Co. Sulfur fugacities at the time of deposition of thvaesite bearing ores were calculated to be 10^-13.8, 10^-11.0-10^-11.7, and 10^-8.7-10^-9.9 atm. at 150°, 200°, and 250°C respectively on the basis of the observed mineral assemblage.

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A new mineral ruthenium in a concentrate from the Horokanai platinum placer, Hokkaido, is described.
Electron-microprobe analysis of this mineral gave the following weight percentages: Ru 64.43, Ir 14.62, Pt 9.14, Rh 7.05, Os 5.29, Pd 0.49, Fe 0.21, Ni tr., Cu tr., total 101.23. The result corresponds to the composition Ru_1.47Ir_0.18Rh_0.16Pt_0.11Os_0.06Pd_0.01Fe_0.01, and the proportions between three prin-cipal metals are Ru:Ir:Rh=81.5:9.7:8.8, which falls in the region of mineral ruthenium because Ru content is more than 80 atomic percent of the three elements. This mineral is, therefore, named ruthenium after its chemical composition.
Reflection colour is white with light creamy tint, and reflectivity is about 60 percent. It shows optically weak anisotropism. It occurs as a tabular crystal associated with rutheniridosmium in the peripheral area of a platinum grain. The size of the crystal is 35×7 microns in polished section.
The mineral ruthenium and the name have been approved by the Commission of New Minerals and Mineral Names, IMA.

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Eleven weak absorption peaks of Fe³⁺ and two broad absorptions of Cr³⁺ doped in synthetic yttrium-aluminium-garnets, Y₃Al₂A1₃O₁₂, have been assigned to d-d transitions of the metal ions in octahedral and tetrahedral sites. All of these absorption peaks have 1:1 correspondence to transitions which are predicted to occur in lower energy region by energy level diagrams.
Intensity analysis of Y₃Al₂A1₃O₁₂: Fe (III) spectra reveals that the ratio of site occupancy of Fe³⁺ between octahedral and tetrahedral positions is approximately 100:1.

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Eighteen wollastonites in the system CaSiO₃-CaMgSi₂O₆ were synthesized from glass and their unit cell dimensions and infra-red absorption spectra have been examined (Tables 3 and 4). The Mg-wollastonite with the diop-side composition crystallized initially from the glass has anomalous axial length b and volume as shown in Fig. 4. These values decrease continuously with increase of the duration of heating (Fig. 3) and are finally invered to those of diopside. In wollastonite between Wo100 and Wo85, which was synthesized stably, linear contractions of cell dimensions are observed due to the replacement of Ca by Mg, but no remarkable change occurs in the infra-red absorption spectra (Figs. 4 and 5). In Mg-wollastonite between Wo80 and Wo0, which is considered to be metastable, an anisotropic contraction of the cell dimensions and linear changes in the wave number of absorption bands are caused by the replacement of Ca by Mg. Especially, the b length along the chain direction and the axial angle β show abnormal variations which may be attributed to the instability of wollastonite structure.
In the course of crystallization of glass, a structural change from Mg-wollastonite to clinopyroxene was observed. The change from pyroxenoid to pyroxene is of special interest, because it may be interpreted by the “transformation mechanism of dense zone preservation” proposed by Morimoto et al. (1966).

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Cation distribution and local variation of site symmetry of the series, Fe₃O₄-Fe₂TiO₄, were studied on two types of specimen synthesized at different temperatures by means of X-ray techniques and the Mössbauer effect. It was ascertained by the least-squares method applied to X-ray diffraction data that Ti⁴⁺ ions are all located at the octahedral sites. Further, a temperature dependence of Fe²⁺-Fe³⁺ distributions over two cation sites was recognized from the variations of the tetrahedral cation-oxygen distances with composition. On the other hand the line-broadening of the Mössbauer spectra indicates that locally varying environments around the cation sites occur in the specimen rich in Ti, and isotropic temperature factor of oxygen showed a rapid increase with Ti content, which may be attributed to the positional disorder of oxygen atoms under such local distortions.

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