Fourteen samples of the so-called garnierite from New Caledonia have been examined by means of X-ray diffraction, electron microscopy and diffraction, chemical and spectrochemical analyses, infrared absorption, differential thermal analysis and heat treatment. The presence of antigorite (platy serpentine), “talc”, chrysotile (fibrous serpentine) and chlorite type minerals has been affirmed. The results of chemical analysis, infrared absorption and differential thermal analysis correlate to those structural types. Neither sepiolite nor nickel-bearing saponite, pimelite, has been found. Especially, the common occurrence of pimelite is rather doubtful. The results of attempt to synthesize nickel hydrosilicate are also presented.

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Datolite of the Ginjiki deposit of the Obira mine is white to pale greenish white in colour and massive, occurring in association with skarn minerals. Refractive indices are: α=1.6273, β=1.652 ?? 1.655, γ=1.666, and (-)2V is 73°±1.5°. The chemical composition is as follows; SiO₂ 37.64, Al₂O₃ 0.32, FeO 0.22, MnO none, CaO 34.90, MgO 0.60, B₂O₃ 21.31, H₂O(+) 5.66, total 100.65%. Trace of Ge is also contained. When weathered, it alters to a clayey mineral and decreases in the B₂O₃ content. It is paragenetic with quartz, calcite, stilpnomelane and grunerite (?), and includes or replaces skarn minerals of earlier stage. Hence, it must have been formed under hydrothermal condition in a relatively later stage of mineralization.

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Manganpyrosmalite (Mn, Fe)₈Si₆O₁₅(OH, Cl)₁₀ occurs abundantly as ore forming mineral at the Shinsanjin ore body of the Kyurazawa mine, Tochigi Prefecture, Japan. The first occurrence of pyrosmalite in Japan has been reported from another ore body of the same mine. The chemical analysis of the newly found manganpyrosmalite by J. Ito gave SiO₂ 35.43, FeO 9.57, MnO 42.01, MgO 1.14, Al₂O₃ 0.50, Cl 5.00, SO₃ 0.17, H₂O(±) 7.50, -O=Cl₂ -1.13, total 100.19%. Sp. gr. 3.12, hardness 41/2; ε=1.631, ω=1.667, ω-ε=0.036, uniaxial negative; lattice constants measured from the X-ray powder pattern are a₀=13.42Å, and c₀=7.159Å. The associated minerals are rhodonite, manganese amphibole, garnet, mangancalcite, quartz and small amounts of sulphide minerals. The chemical analysis of previously reported pyrosmalite from the Odaki ore body in this mine by H. Haramura came out as follows; SiO₂ 33.50, TiO₂ 0.08, Al₂O₃ 0.11, Fe₂O₃ 1.07, FeO 24.09, MnO 27.62, MgO 1.65, ZnO 0.04, CaO ?? 0.02, H₂O(-) 0.22, H₂O(+) 6.53, P₂O₅ ?? 0.02, Cl 5.63, -O=Cl₂ -1.27, total 99.31%. The correlation between the refractive indices and FeO contents of the minerals of friedelite-manganpyro-smalite-pyrosmalite series is given.

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A black prismatic kobeitc-like mineral from a granite pegmatite of the Ushio mine in Ômiya town, Kyoto Prefecture and the kobeite from the original locality have been studied. Both the chemical analyses and the X-ray powder patterns of heated materials of the two minerals gave the concordant results. The two minerals contain notable amount of zirconium and after heat treatment give X-ray patterns similar to those of stabilized cubic zirconia.
Kobeite will not be a member of the euxenite-polycrase series but may be a distinct mineral species of multiple oxide containing Y, Fe, U, Ti, Zr and Nb as the main components.

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A new mode of occurrence of cosalite from Japan and its mineralogical properties are described. The mineral was identified by X-ray studies and chemical analyses. It occurs in a bedded type manganese deposit in a Palaeozoic formation. Acicular crystals were found in a vug of rhodonite with quartz or growing on the surface of quartz crystals. The cosalite is associated with such metallic minerals as gersdorffite, niccolite, huebnerite, scheelite, sphalerite, galena, pyrrhotite, uraninite, etc., as well as manganese minerals.
X-ray and crystallographic data, optical properties, etch tests and chemical analysis are presented. Cell constants: a₀=19.09Å., b₀=23.89Å. and c₀=4.058Å. Space group: D¹⁶_2h-Pbnm.

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Yoshimuraite, a new barium-titanium-manganese complex silicate mineral, was found in an alkali-pegmatitic facies bordering the bedded manganese deposit of the Misago ore body of the Noda-Tamagawa mine. Yoshimuraite occurs as dark-brownish platy to tabular crystals, or sometimes in the stellate groups embedded in coarse aggregates of barium-bearing potashfeldspar, quartz, richterite, urbanite, rhodonite etc.
It resembles lamprophyllite and astrophyllite which usually occur in alkali-pegmatites. It is orange brown in colour, brittle and has a perfect cleavage parallel to {010} and distinct cleavages on {10 _?? } and {101}. Polysynthetic twinning on {010} is common. Hardness, 41/2; Sp. gr., 4.13 (obs.) and 4.21 (calc.). Triclinic, with a₀=7.00, b₀=14.71, c₀=5.39Å, α=93.5°, β=90.2°, γ=95.3°, and a:b:c=0.476:1:0.366. Space group, P _?? . Biaxial positive with α=1.763, β=1.777, γ=1.785, (+)2V=85°-90° ρ⟩υ, and absorption X⟨Y ?? Z. Optical orientation, γ′ nearly parallel to c-axis, α′ nearly parallel to a-axis. Pleochroism, α bright yellow, β orange-brown, γ brown.
Chemical analysis by J. Ito gave SiO₂ 18.25, TiO₂ 10.00, Fe₂O₃ 1.32, FeO 1.47, MnO 17.64, MgO 0.56, ZnO 0.50, BaO 33.51, SrO 4.62, Na₂O 0.16, K₂O 0.03, P₂O₅ 3.98, SO₃ 5.40, Cl 0.41, H₂O(±) 2.34, less for Cl 0.09, total 100.10%. The results indicate a formula of approximately X₂Y₂ (Ti, Fe) O (Si₂O₇) ?? (P, S)O₄ ?? (OH) or X₂Y₂ (Ti, Fe) (SiO₄)₂ ?? (P, S)O₄ ?? (OH), where X=Ba, Sr and Na, Y=Mn, Fe, Mg and Zn.
The mineral is named after Professor Toyofumi Yoshimura who has contributed much to the study of manganese minerals in Japan.

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