Morphological, optical and X-ray properties of several stones in glass were described and considerations were made of the geneses of these stones.
It has been found that the difference in the variety of the stones arises from the difference in compositions of molten glass itself and/or of refracory bricks. In addition, foreign materials which have been captured in the molten glass also affect the character of stones.
The writer found new occurrences of aegirine, celsian, hercynite and spinel in stones.⁄⁄⁄

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The variation of unit cell parameters in the wolframite series has been investigated on the specimens synthesized by fusion of various mixtures of FeCl₂•4H₂O, MnCl₂•4H₂O and Na₂WO₄•2H₂O. The results show that a₀, b₀ and c₀ increase almost linearly with increasing MnO content as follows: from a₀=4.732Å, b₀=5.707Å and c₀=4.965Å in FeWO₄ to a₀=4.834Å, b₀=5.758Å and c₀=4.999Å in MnWO₄. Angle β varies also gradually from 90°00′ in FeWO₄ to 91°11′ in MnWO₄. However, it appears that the value of 90°00′ is maintained in the range from FeWO₄ to about (Fe_0.9Mn_0.1)WO₄. The measurement has also been carried out on six natural specimens whose chemical data had been available. The unit cell parameters of these natural wolframites appear to follow the same variation diagram obtained with the synthetic specimens, although some numerical deviations are unavoidable. The differences between the result of chemical analysis and the composition determined by using the variation diagram are within the range of ±6 molper cent.

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Ikunolite, Bi₄(S, Se)₃, a new mineral from the Ikuno mine occurs in ferberite-bismuth-bismuthinite quartz vein. It belongs to rhombohedral system with a_rh=13.28Å, ?? =18°00′, Z=1 (or a₀=4.15Å, c₀=39.19Å, Z=3 in hexagonal lattice) and the space group is R ?? 3m. Physical and optical properties are: lead grey in colour and dark grey in streak colour; hardness 2, very flexible; specific gravity=7.97 (calc.), 7.8 (meas.); perfect cleavage parallel to {0001}; anisotropic in the section diagonal to the basal cleavage and etched by HNO₃ and FeCl₃ solution. Chemical analysis gives Bi_3•79 (S_2•76Se_0•24)_3.00 close to Bi₄ (S, Se)₃ with S:Se=92:8. The sheet structure determined by single crystal method is closely related to the other rhombohedral chalcogenides of bismuth. Ikunolite resembles joseite A [Bi₄TeS₂] in structure, crystallography and optical properties and belongs to the same group of bismuth-chalcogenide minerals with Bi:(S, Se, Te)=4:3.

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The ore deposits of the Noda-Tamagawa mine have become famous for their wealth of mineral species, the production of high grade manganese ores, and also the recent discovery of uranium ores. More than seventy minerals have been found in this mining area including such rare minerals as pyrochroite, manganosite, vredenburgite, yoshimuraite (a new mineral of Ba, Sr, Mn, Ti-silicate), etc.
The ore deposits of this mine may be classified into the following types:
(A) The contact-metamorphosed bedded manganese deposits in metamorphosed roof pendant in the batholithic mass of granitic rocks.
(B) (1) The uranium-bearing veins.
(2) The cobalt-nickel-molybdenum-bearing uranium deposits associated with pelitic hornfels.
(C) Pyrometasomatic copper-bearing pyrrhotite deposits found in limestone.
(D) Gold-silver-bearing quartz-arsenopyrite veins.
Among them manganese deposits are economically the most important ones. The geology and ore deposits of the mine are briefly described. The mineral parageneses of ores and country rocks are shown in Tables 1 and 2.

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