A BASIC program to calculate the Schreinemakers' bundle is designed for NEC 9800 series computer. Algorithms for determining stable univariant lines and combing stable invariant points are newly devised following the graphic theory. The computer program can solve all possible sets of invariant points in model systems with up to (C+5) phases. For model (C+3) phases systems, the program automatically displays all possible nets on a video screen.

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Oolitic opal (siliceous oolite) and massive opal from Tateyama Hot Spring Shin-yu, Toyama Prefecture, Central Japan, have been investigated based on mineralogy, geochemistry, and SEM-observations.
Both oolitic opal and massive opal are composed of amorphous spherical silica particles. Individual oolitic opals ups to their diameter to 10mm have cores of rock or mineral fragments. Each silica particles of oolitic opal or massive opal increased their diameter by combinations of smaller ones that assimilated each other by changing their forms. Oolitic opal and massive opal are ultimately the same.
The water of the hot spring showing about 70°C, pH=3 and over-saturated with silica, contains abundant small silica particles. Oolitic opal and massive opal are precipitating at the Tateyama Hot Spring Shin-yu now.
Some of siliceous oolites found in Japan would be formed through the same mechanism and circumstances such as Tateyama Hot Spring Shin-yu.

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The Kokkaibashi plutonic rocks from the northeastern edge of the Akaishi Mountains, central Japan, were dated by the K-Ar method with two hornfels in the contact aureole. The ages of the intrusions of the Kokkaibashi plutonic masses and the Kaikomagatake granitic body are in the ranges of 22.4-12.6 Ma and 13-11 Ma, respectively. These two igneous activities might be strong-ly influenced by geotectonic movement of the Shimanto Belt within the Akaishi Mountains. The beginning of the igneous activity of the Kokkaibashi plutons predated the formation of the Itoigawa-Shizuoka Tectonic Line, and was contemporary with the development of the Japan Sea Basin.

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Monohydrocalcite from Shiowakka occurs as a constituent of calcite-dominant sinter precipitated in cold (14.5-17.8°C) saline (Mg²⁺ ?? 4, 000mg/l, Cl^- ?? 4, 000mg/1) spring water with pH=6.67 and Mg²⁺/Ca²⁺=0.64. The idiomorphs under SEM are trigonal bipyramid with (Ca_0.979 Fe²⁺0.013Mg_0.005(Na₂)_0.003) as the cationic counterpart, where the relation Fe2+>Mg in mole ratio is new to this mineral in contrast to Mg>Fe²⁺ in all the known monohydrocalcite analyses. The X-ray powder diffraction pattern is indexed on a hexagonal cell with ?? =10.566Å and ?? =7.565Å, where a subcell with ?? = ?? /√3 is prominent. The closer occurrence with algae indicates the precipitation favoured by its existence.

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