The measurement of the effective porosity (φ _e) of non-coated and side-coated intact granite cores (diameter: 4 cm; length: 0.5 to 20 cm) revealed that (φ _e) is almost constant around 0.74% for all the cores. The coloring experiment of small pores in the intact granite core revealed that the pores are mainly distributed around and inside feldspars. The measurement of effective porosities of biotite, quartz and K-feldspar from pegmatite indicates that K-feldspar has a largest φ _e of about 2% among these pegmatite minerals.
These results suggest the homogeneous and continuous distribution of small pores, mainly around and inside feldspars, in the intact granite core. Consequently, the intact granite can be treated as a kind of homogeneous porous media for the study of material transport such as the matrix diffusion of radionuclides which are supposed to be released with groundwater flows through fracture networks from the radioactive waste repository.

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Toyoha lead-zinc-silver vein-type deposit in Hokkaido, Japan produces an important amount of indium as well as tin and copper. Bismuth, tungsten, antimony, arsenic, and cobalt are minor but common metals. Indium minerals recognized are; unnamed Zn-In mineral (hereafter abbreviated as ZI) whose composition is at the midst of sphalerite and roquesite, unnamed Ag-In mineral (AI) of AglnS ₂ composition, roquesite (RQ) and sakuraiite. Observed maximum weight percentages of indium in chalcopyrite, kesterite (KS) and stannite are 1.0, 1.86 and 20.0, respectively. Indium concentration in sphalerite ranges from O.On to a few weight percent in most case, but exceeds ten weight percent at some points. Detailed EPMA analyses have revealed that such high concentration is attributed to a continuous solid solution between sphalerite (SP) and ZI. Continuous solid solutions between RQ ₉₀ZI ₁₀ and RQ ₃₇ZI ₆₃, and between KS ₁₀₀ZI ₀and KS ₃₀ZI ₇₀ are also detected. These solid solutions are attributed to coupled substitutions of 2(Zn, Fe) for CuIn, and of (Zn, Fe)In for CuSn. Other substitutions found between chalcopyrite and stannite and between stannite/kesterite and roquesite are of (Fe ⁺², Zn)Sn for 2Fe ⁺³ and of (Fe ⁺², Zn)Sn for 2In respectively. Economically most important indium carriers in Toyoha are ZI and indium-bearing sphalerite. Next to sphalerite are kesterite, stannite and the anisotropic chalcopyrite. The occurrence of these minerals indicates that these minerals have been formed by pulsatile mineralization whose peak temperatures were 50 to 100°C higher than the hitherto estimated maximum formation temperature, about 300°, of the deposit.

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The Toyoha Vein type Pb-Zn ore deposit occurs in the Neogene Tertiary andesitic volcanics. The studies of geochemistry and alteration on wall rocks revealed that the mineralized zone is indicated by following three anomalies.
·high MnO concentration
·high F concentration
·the lack of plagioclase and calcite.
These anomalies always overlap near the veins on the underground mining levels. On the other hand, only local anomalies are found on the surface, because most of the veins of the Toyoha ore deposit are blind and have no outcrop. For this reason, the relationship between the surface anomalies and the location of blind veins is obscured. This fact im-plies that blind vein does not always exist right under the surface anomaly, and that we should not abandon the circumference area of the anomaly.

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The Sambo Pb-Zn-Barite deposit belongs to a fissure filling vein type. The present study represents that the mineralized stages are classified into the four (I, II, III and IV). Major constituent minerals of each stage are as follows: quartz and sulfides (stage I), barite (stage II), quartz and sulfides (stage III) and quartz (stage IV).
The ranges of filling temperature of fluid inclusions for stages I and III are very similar (90° to 300°C for stage I and 120° to 310°C for stage III), while the range for stage II (110° to 260°C) is slightly lower than those for stages I and III. However, the salinity for stage II (8.7 to 11.8 wt% NaCl eq.) is higher than those for stage I (1.1 to 5.1 wt% NaCl eq.) and stage III (2.3 to 5.7 wt% NaCl eq.). The higher salinity for stage II (barite-forming stage) suggests the possibility of mixing of original fluid with high saline, Ba-rich solution (probably connate water origin). And the mixing may be responsible for the slightly lower range of filling temperature for stage II than those for stages I and III. Stage IV, the latest stage, shows the lowest range of filling temperature (110° to 170°C).

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Chlorite, which occurs commonly as a gangue mineral in four hydrothermal vein deposits, that is, Chitose, Yatani, Sado and Ohe, was quantitatively analyzed by X-ray microanalyser. Chlorite from Yatani, Sado, and Ohe, is Fe-rich, while chlorite from Chitose is Mg-rich. The chlorite geothermometer (WALSHE, 1986) applied to these vein chlorites gives temperatures equivalent to or slighly lower values than those obtained by fluid inclusion thermometry. They contain a large or small amount of manganese (maximum MnO content 17.5 wt. % at Sado deposit), and show Fe-Mn compositional variation at more or less constant MgO content in each vein. This is probably owing to their difference of time and space of chlorite formation. For example, the activity of Fe ²⁺ ion relative to that of Mn ²⁺ ion in hydrothermal solution decreases with temperature lowering at Chitose and Yatani deposits. While, the activity ratio increases with decreasing temperature at Sado and Ohe deposits.
The exchange of Fe ²⁺ and Mn ²⁺ between chlorite and hydrothermal solution is a function of physicochemical parameters (e.g. temperature, oxygen fugacity, pH, total dissolved sulfur, and activity of Mn ²⁺ and Fe ²⁺ ions in aqueous solution). It is inferred that the compositional variation of chlorite in a vein might be influenced by the local or temporal changes of hydrothermal environments, such as oxidation-reduction state and/or temperature.

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Neogene mineralization related to the formation of magnetite skarns and manganese, lead, zinc and silver veins at the Matahachi deposit in the Jokoku-Katsuraoka mining area is summarized on the basis of macrostructures and mineral paragenesis of individual ore bodies, mineralization stages, hypogene zoning and environment of ore formation.
The mineralization sequence, from earlier to later, is divided into five stages as follows; Stage I: formation of magnetite skarns, Stage II: formation of Pb-Zn-(Cu) quartz veins, Stage III: formation of Pb-Zn-(Mn) quartz veins, Stage IV: formation of (Pb)-(Zn) rhodochrosite veins, rhodochrosite veins and massive rhodochrosite deposits and Stage V: formation of ferromanganoan dolomite veins. Mineralization of stages (I) through (V) at the Matahachi deposit is closely related to the mineralization events showing polyascendent zoning.
Three major kinds of vein deposits at the Matahachi deposit include Pb-Zn-(Mn) quartz veins, well-crusted banding (Pb)-(Zn) rhodochrosite veins and rhodochrosite veins. Ore types such as Pb-Zn, well-crusted banded rhodochrosite and rhodochrosite ores are correlated with ore grade. Based on ore grade, the three zones are arranged from the northwestern to southeastern part of the deposit in the order of Pb-Zn, Intermediate and Rhodochrosite zones. Pb-Zn-(Mn) quartz veins tend to occur in the Pb-Zn zone of the deposit, while rhodochrosite veins are widely distributed in the Rhodochrosite zone. Horizontal and vertical zoning could be formed by polyascendent mineralization related to formation of Pb-Zn-(Mn) quartz, (Pb)-(Zn) rhodochrosite and rhodochrosite veins.
Formation temperatures gradually decrease from earlier to later stages at the Matahachi deposit. Changes of formation temperatures correspond to the progress of mineralization stages associated with multiple mineralization.

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