Superior chinoopyrxene analyses show that chinopyroxenes of low Ca content have relatively low Al, while calcic chinopyroxenes are variable in Al content. The variation of Al content is related to the Fe₂O₃/FeO ratios in clinopyroxenes, as well as to the silica saturation of magmas from which they crystallize. The Si-Al replacement in clinopyroxenes is thought to be related to conditions of oxidation, and controlled by the entrance of Fe³⁺ ions the chinopyroxene structure.

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The Kanmuri plateau is composed of basaltic rocks belong-ing to both alkaline and calc-alkaline rock series of Pleistocene to Recent time, lying on the Paleozoic sediments and Cretaceous granitic rocks. The order of the lava succession is as follows: picrite-basalt, olivine basalt and trachybasalt of alkaline series, hornblende basalt and andesite of calcalkaline series. Among of them, the last one is the most abundant.
The petrographic and petrochemical studies indicate that the calcalkaline volcanic rocks are derived from an olivine basalt magma which has assimilated basement granitic rocks.

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The Kômori Ultrabasic Mass is located in the northern side of the Maizuru Zone, Kyoto Prefecture. It is mainly composed of serpentinized dunite being accompanied with such rocks as peridotite, pyroxenite, gabbro, diabase and albitite. At Komori mine, the writer found apophyllite in a druse of albitite in serpentinite mass. Near the Komori ore mineral deposit, serpentinization is remarkably observed.
Apophyllite crystals are colorless and their maximum size is 2mm in length. The optical properties are variable; uniaxial positive, uniaxial negative or biaxial positive; these crystals coexist in a druse and the uniaxial positive crystals are often enclosed regularly in the uniaxial negative crystals.
Refractive indices and X-ray powder patterns are well coincident with data of apophyllite so far reported. Thermal analysis data are also shown in this paper.

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A triangular etch pit on abasal cut of quartz, which was artificially made in dil. HF solution, is formed by three inner faces. The corner of triangle pit orientates to the left for a right handed quartz as shown in Figure 1 illustrating the arrangement of Si atoms. It can be considered from the figure that the inner face was made by the unit cell etching. The etch velocity along to the a₀ axis is similar ratio to it along to the c₀ axis, Thus, the Miller indices of inner face can be determined from Figure 2 as ξ[1122] by calculation of tan ρ=c₀/a₀ and also ρ=47°44' thereof. The orientations of etch pit on natural r and z faces are similar to the projections of basal pit on both r and z planes as Figure 3. The etch pits of left handed quartz, which are saved in the article, are enantiomorphic reversal in all figures.

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