The zeolite tuffs from Lake To jo in “Paleo Setouchi Region” were studied compared with those from Tamatsukuri Hot Spring Area in “Green Tuff Region”. The materials were from Yashiro and Tojo cho, Kato-gun, Hyogo Prefecture. The zeolite tuffs develop in Ogo, Yokawa and Arino formations in Kobe groups of the Miocene age, and are covered by weathered conglomerate of the Alluvial age called Osaka groups. The zeolite tuffs mainly consist of clinoptilolite and contain no mordenite. Purified material and ion-exchanged materials were investigated by means of X-ray diffractometry, chemical and thermal analyses, especially by “Differential Scanning Calorimetry” for the calculations of dehydration energy. It was found that the present zeolite in Lake Tojo are malcrystallized state and are supposed to have been formed in the shallower part than those from Tamatsukuri Hot Spring Area. The present zeolite tuff may have beem formed by the reaction of diageneses of acidic volcanic ash, such as rhyolite and dacite, with thermal water like hot spring in this area.

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Mn K EXAFS analyses were carried out on synthetic manganoan fluoromicas and glasses. These glasses were quenched from the melts of the respective starting mixtures used for syntheses of the mica crystals. The crystals showed inverse pleochroism compared with ordinary micas. Sr₂MnGe₂O₇ and MnCO₃ were used as reference materials to Mn²⁺ ions coordinated by four oxygens and by six oxygens, respectively, in the EXAFS analyses. The average Mn-O distances were estimated by the curve-fitting method to be 2.11-2.13 Å in the micas and 2.06-2.10 Å in the glasses. These values indicate that a port of Mn²⁺ ions are in tetrahedral coordinations. The inverse pleochroism is supposed to be due to the existence of Mn²⁺ ions at the tetrahedral sites in the mica structures. The obtained Mn-O distances suggest that the coordination number of Mn²⁺ ions is greater in mica crystals than in the melts, from which micas crystallize out.

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It is widely believed that ZrO₂ refractory can not be available without being stabilized or partially stabilized because of its large volume change derived from its monoclinic-tetragonl-cubic transition. This concept can generally be acceptable in fired refractory where monoclinic-tetragonal transition occures reciprocatingly during firing process. On the contrary, the concept can not necessary be acceptable in fusion cast refractory because aforementioned transition can only once be experienced unreciprocatingly during cooling process from melt to solid and also this transition is not accompanied with volume contraction causing tensile stress. Authors, on the basis of up-dated data and informations, give a commentary on the monoclinic ZrO₂ refractory which is now widely applied in glass industries.

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This thesis deals with the Greek-Roma and Middle Age's writings on natural history of mineral kingdom, the ancient metallurgy and the use of minerals as medicines, giving a historical outline of the formative period through which the early sciences and techology on minerals were developed. The ides of science and technology fostered by Georgius Aglicola, a great naturalist and architect in the Runaissance age, is mentioned in this paper. He was a person who started his scientific research at dawn of the modern science and technology andd established the basis of both. In the seventeeth century, modern scientific research had already been afoot, and the science on the mineral kingdom, especially crystallomorphology and crystal physics began to be studied. The scientific description of the genesis and formation of minerals commenced. So this century was the preparatory stage of the efflorescence to the mineralogy of the eighteenth century.

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This paper reviews recent experimental studies on high-pressure phase equilibria and physical properties of minerals relevant to the earth's mantle. On the basis of these currently availabtle data, a mineral physics test has been made, in which seismic velocity and density changes associated with the phase transformations in a pyrolite composition are compared with those derived from geophysical observations. The results show that the calculated velocity and density profiles for the pyrolite mantle agree well with the observed distributions throughout the upper mantle and the transition region. These profiles for the lower mantle conditions, however, are only poorly defined to date, because of large uncertainties attached to the measurements of the mineral physics parameters. Thus further experimental studies, particularly measurements of pressure and temperature dependence of elastic properties for high-pressure phases, are required for evaluation of the hypotheses on chemical composi-tion and constitution of the lower mantle.

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